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Abstract
This manual describes MySQL Connector/J, the JDBC implementation for communicating with MySQL servers.
Document generated on: 2011-10-02 (revision: 27532)
Table of Contents
List of Tables
List of Examples
DriverManagerSELECT queryConnection.prepareCall()CallableStatement input
parametersAUTO_INCREMENT column values
using Statement.getGeneratedKeys()AUTO_INCREMENT column values
using SELECT LAST_INSERT_ID()AUTO_INCREMENT column values
in Updatable ResultSetsMySQL provides connectivity for client applications developed in the Java programming language through a JDBC driver, which is called MySQL Connector/J.
MySQL Connector/J is a JDBC Type 4 driver. Different versions are available that are compatible with the JDBC 3.0 and JDBC 4.0 specifications. The Type 4 designation means that the driver is pure-Java implementation of the MySQL protocol and does not rely on the MySQL client libraries.
Although JDBC is useful by itself, we would hope that if you are not familiar with JDBC that after reading the first few sections of this manual, that you would avoid using naked JDBC for all but the most trivial problems and consider using one of the popular persistence frameworks such as Hibernate, Spring's JDBC templates or Ibatis SQL Maps to do the majority of repetitive work and heavier lifting that is sometimes required with JDBC.
This section is not designed to be a complete JDBC tutorial. If you need more information about using JDBC you might be interested in the following online tutorials that are more in-depth than the information presented here:
JDBC Basics: A tutorial from Sun covering beginner topics in JDBC
JDBC Short Course: A more in-depth tutorial from Sun and JGuru
Key topics:
For help with connection strings, connection options setting up your connection through JDBC, see Section 4.1, “Driver/Datasource Class Names, URL Syntax and Configuration Properties for Connector/J”.
For tips on using Connector/J and JDBC with generic J2EE toolkits, see Section 5.2, “Using Connector/J with J2EE and Other Java Frameworks”.
Developers using the Tomcat server platform, see Section 5.2.2, “Using Connector/J with Tomcat”.
Developers using JBoss, see Section 5.2.3, “Using Connector/J with JBoss”.
Developers using Spring, see Section 5.2.4, “Using Connector/J with Spring”.
Developers using GlassFish (Sun Application Server), see Section 5.2.5, “Using Connector/J with GlassFish”.
Table of Contents
There are currently four versions of MySQL Connector/J available:
Connector/J 5.1 is the Type 4 pure Java JDBC driver, which
conforms to the JDBC 3.0 and JDBC 4.0 specifications. It
provides compatibility with all the functionality of MySQL,
including 4.1, 5.0, 5.1, 5.4 and 5.5. Connector/J 5.1 provides
ease of development features, including auto-registration with
the Driver Manager, standardized validity checks, categorized
SQLExceptions, support for the JDBC-4.0 XML processing, per
connection client information,
NCHAR,
NVARCHAR and
NCLOB types. This release also includes all
bug fixes up to and including Connector/J 5.0.6.
Connector/J 5.0 provides support for all the functionality offered by Connector/J 3.1 and includes distributed transaction (XA) support.
Connector/J 3.1 was designed for connectivity to MySQL 4.1 and MySQL 5.0 servers and provides support for all the functionality in MySQL 5.0 except distributed transaction (XA) support.
Connector/J 3.0 provides core functionality and was designed with connectivity to MySQL 3.x or MySQL 4.1 servers, although it will provide basic compatibility with later versions of MySQL. Connector/J 3.0 does not support server-side prepared statements, and does not support any of the features in versions of MySQL later than 4.1.
The following table summarizes the Connector/J versions available:
| Connector/J version | Driver Type | JDBC version | MySQL Server version | Status |
|---|---|---|---|---|
| 5.1 | 4 | 3.0, 4.0 | 4.1, 5.0, 5.1, 5.4, 5.5 | Recommended version |
| 5.0 | 4 | 3.0 | 4.1, 5.0 | Released version |
| 3.1 | 4 | 3.0 | 4.1, 5.0 | Obsolete |
| 3.0 | 4 | 3.0 | 3.x, 4.1 | Obsolete |
The current recommended version for Connector/J is 5.1. This guide covers all four connector versions, with specific notes given where a setting applies to a specific option.
The following table summarizes Connector/J Java dependencies:
| Connector/J version | Java RTE required | JDK required (to build source code) |
|---|---|---|
| 5.1 | 1.5.x, 1.6.x | 1.6.x and 1.5.x |
| 5.0 | 1.3.x, 1.4.x, 1.5.x, 1.6.x | 1.4.2, 1.5.x, 1.6.x |
| 3.1 | 1.2.x, 1.3.x, 1.4.x, 1.5.x, 1.6.x | 1.4.2, 1.5.x, 1.6.x |
| 3.0 | 1.2.x, 1.3.x, 1.4.x, 1.5.x, 1.6.x | 1.4.2, 1.5.x, 1.6.x |
MySQL Connector/J does not support JDK-1.1.x or JDK-1.0.x.
Because of the implementation of
java.sql.Savepoint, Connector/J 3.1.0 and
newer will not run on a Java runtime older than 1.4 unless the
class verifier is turned off (by setting the
-Xverify:none option to the Java runtime). This
is because the class verifier will try to load the class
definition for java.sql.Savepoint even
though it is not accessed by the driver unless you actually use
savepoint functionality.
Caching functionality provided by Connector/J 3.1.0 or newer is
also not available on JVMs older than 1.4.x, as it relies on
java.util.LinkedHashMap which was first
available in JDK-1.4.0.
If you are building Connector/J from source code using the source distribution (see Section 2.4, “Installing from the Development Source Tree”) then you must use JDK 1.4.2 or newer to compile the Connector package. For Connector/J 5.1 you must have both JDK-1.6.x. and JDK-1.5.x installed to be able to build the source code.
Table of Contents
You can install the Connector/J package using either the binary or
source distribution. The binary distribution provides the easiest
method for installation; the source distribution enables you to
customize your installation further. With either solution, you
must manually add the Connector/J location to your Java
CLASSPATH.
If you are upgrading from a previous version, read the upgrade information before continuing. See Section 2.3, “Upgrading from an Older Version”.
Connector/J is also available as part of the Maven project. More information, and the Connector/J JAR files can be found at the Maven repository.
The easiest method of installation is to use the binary
distribution of the Connector/J package. The binary distribution
is available either as a Tar/Gzip or Zip file which you must
extract to a suitable location and then optionally make the
information about the package available by changing your
CLASSPATH (see
Section 2.2, “Installing the Driver and Configuring the CLASSPATH”).
MySQL Connector/J is distributed as a .zip or .tar.gz archive
containing the sources, the class files, and the JAR archive
named
mysql-connector-java-,
and starting with Connector/J 3.1.8 a debug build of the driver
in a file named
[version]-bin.jarmysql-connector-java-.
[version]-bin-g.jar
Starting with Connector/J 3.1.9, the .class
files that constitute the JAR files are only included as part of
the driver JAR file.
You should not use the debug build of the driver unless
instructed to do so when reporting a problem or a bug, as it is
not designed to be run in production environments, and will have
adverse performance impact when used. The debug binary also
depends on the Aspect/J runtime library, which is located in the
src/lib/aspectjrt.jar file that comes with
the Connector/J distribution.
You will need to use the appropriate graphical or command-line utility to extract the distribution (for example, WinZip for the .zip archive, and tar for the .tar.gz archive). Because there are potentially long file names in the distribution, we use the GNU tar archive format. You will need to use GNU tar (or an application that understands the GNU tar archive format) to unpack the .tar.gz variant of the distribution.
Once you have extracted the distribution archive, you can
install the driver by placing
mysql-connector-java-[version]-bin.jar in
your classpath, either by adding the full path to it to your
CLASSPATH environment variable, or by
directly specifying it with the command line switch -cp when
starting your JVM.
If you are going to use the driver with the JDBC DriverManager,
you would use com.mysql.jdbc.Driver as the
class that implements java.sql.Driver.
You can set the CLASSPATH environment
variable under UNIX, Linux or Mac OS X either locally for a user
within their .profile,
.login or other login file. You can also set
it globally by editing the global
/etc/profile file.
For example, under a C shell (csh, tcsh) you would add the
Connector/J driver to your CLASSPATH using
the following:
shell> setenv CLASSPATH /path/mysql-connector-java-[ver]-bin.jar:$CLASSPATH
Or with a Bourne-compatible shell (sh, ksh, bash):
shell> export set CLASSPATH=/path/mysql-connector-java-[ver]-bin.jar:$CLASSPATH
Within Windows 2000, Windows XP, Windows Server 2003 and Windows Vista, you must set the environment variable through the System Control Panel.
If you want to use MySQL Connector/J with an application server
such as GlassFish, Tomcat or JBoss, you will have to read your
vendor's documentation for more information on how to configure
third-party class libraries, as most application servers ignore
the CLASSPATH environment variable. For
configuration examples for some J2EE application servers, see
Section 5.2, “Using Connector/J with J2EE and Other Java Frameworks”. However, the
authoritative source for JDBC connection pool configuration
information for your particular application server is the
documentation for that application server.
If you are developing servlets or JSPs, and your application server is J2EE-compliant, you can put the driver's .jar file in the WEB-INF/lib subdirectory of your webapp, as this is a standard location for third party class libraries in J2EE web applications.
You can also use the MysqlDataSource or
MysqlConnectionPoolDataSource classes in
the com.mysql.jdbc.jdbc2.optional package, if
your J2EE application server supports or requires them. Starting
with Connector/J 5.0.0, the
javax.sql.XADataSource interface is
implemented using the
com.mysql.jdbc.jdbc2.optional.MysqlXADataSource
class, which supports XA distributed transactions when used in
combination with MySQL server version 5.0.
The various MysqlDataSource classes
support the following parameters (through standard set
mutators):
user
password
serverName (see the previous section about fail-over hosts)
databaseName
port
We try to keep the upgrade process as easy as possible, however as is the case with any software, sometimes changes need to be made in new versions to support new features, improve existing functionality, or comply with new standards.
This section has information about what users who are upgrading from one version of Connector/J to another (or to a new version of the MySQL server, with respect to JDBC functionality) should be aware of.
Connector/J 3.1 is designed to be backward-compatible with Connector/J 3.0 as much as possible. Major changes are isolated to new functionality exposed in MySQL-4.1 and newer, which includes Unicode character sets, server-side prepared statements, SQLState codes returned in error messages by the server and various performance enhancements that can be enabled or disabled using configuration properties.
Unicode Character Sets:
See the next section, as well as
Character Set Support, for information on this new
feature of MySQL. If you have something misconfigured, it
will usually show up as an error with a message similar to
Illegal mix of collations.
Server-side Prepared Statements: Connector/J 3.1 will automatically detect and use server-side prepared statements when they are available (MySQL server version 4.1.0 and newer).
Starting with version 3.1.7, the driver scans SQL you are
preparing using all variants of
Connection.prepareStatement() to
determine if it is a supported type of statement to
prepare on the server side, and if it is not supported by
the server, it instead prepares it as a client-side
emulated prepared statement. You can disable this feature
by passing
emulateUnsupportedPstmts=false in
your JDBC URL.
If your application encounters issues with server-side prepared statements, you can revert to the older client-side emulated prepared statement code that is still presently used for MySQL servers older than 4.1.0 with the connection property useServerPrepStmts=false
Datetimes with all-zero
components (0000-00-00 ...): These
values can not be represented reliably in Java.
Connector/J 3.0.x always converted them to
NULL when being read from a ResultSet.
Connector/J 3.1 throws an exception by default when these values are encountered as this is the most correct behavior according to the JDBC and SQL standards. This behavior can be modified using the zeroDateTimeBehavior configuration property. The permissible values are:
exception (the default), which
throws an SQLException with an SQLState of
S1009.
convertToNull, which returns
NULL instead of the date.
round, which rounds the date to the
nearest closest value which is
0001-01-01.
Starting with Connector/J 3.1.7,
ResultSet.getString() can be decoupled
from this behavior using
noDatetimeStringSync=true (the
default value is false) so that you can
retrieve the unaltered all-zero value as a String. It
should be noted that this also precludes using any time
zone conversions, therefore the driver will not allow you
to enable noDatetimeStringSync and
useTimezone at the same time.
New SQLState Codes: Connector/J 3.1 uses SQL:1999 SQLState codes returned by the MySQL server (if supported), which are different from the legacy X/Open state codes that Connector/J 3.0 uses. If connected to a MySQL server older than MySQL-4.1.0 (the oldest version to return SQLStates as part of the error code), the driver will use a built-in mapping. You can revert to the old mapping by using the configuration property useSqlStateCodes=false.
ResultSet.getString():
Calling ResultSet.getString() on a
BLOB column will now return
the address of the byte[] array that
represents it, instead of a String
representation of the BLOB.
BLOB values have no
character set, so they cannot be converted to
java.lang.Strings without data loss or
corruption.
To store strings in MySQL with LOB behavior, use one of
the TEXT types, which the
driver will treat as a java.sql.Clob.
Debug builds: Starting
with Connector/J 3.1.8 a debug build of the driver in a
file named
mysql-connector-java-
is shipped alongside the normal binary jar file that is
named
[version]-bin-g.jarmysql-connector-java-.
[version]-bin.jar
Starting with Connector/J 3.1.9, we do not ship the .class files unbundled, they are only available in the JAR archives that ship with the driver.
You should not use the debug build of the driver unless
instructed to do so when reporting a problem or bug, as it
is not designed to be run in production environments, and
will have adverse performance impact when used. The debug
binary also depends on the Aspect/J runtime library, which
is located in the
src/lib/aspectjrt.jar file that comes
with the Connector/J distribution.
In Connector/J 5.0.x and earlier, the alias for a table in
a SELECT statement is
returned when accessing the result set metadata using
ResultSetMetaData.getColumnName().
This behavior however is not JDBC compliant, and in
Connector/J 5.1 this behavior was changed so that the
original table name, rather than the alias, is returned.
The JDBC-compliant behavior is designed to let API users
reconstruct the DML statement based on the metadata within
ResultSet and
ResultSetMetaData.
You can get the alias for a column in a result set by
calling
ResultSetMetaData.getColumnLabel().
If you want to use the old noncompliant behavior with
ResultSetMetaData.getColumnName(),
use the useOldAliasMetadataBehavior
option and set the value to true.
In Connector/J 5.0.x the default value of
useOldAliasMetadataBehavior was true, but
in Connector/J 5.1 this was changed to a default value of
false.
Using the UTF-8 Character Encoding - Prior to MySQL server version 4.1, the UTF-8 character encoding was not supported by the server, however the JDBC driver could use it, allowing storage of multiple character sets in latin1 tables on the server.
Starting with MySQL-4.1, this functionality is deprecated. If you have applications that rely on this functionality, and can not upgrade them to use the official Unicode character support in MySQL server version 4.1 or newer, you should add the following property to your connection URL:
useOldUTF8Behavior=true
Server-side Prepared Statements - Connector/J 3.1 will automatically detect and use server-side prepared statements when they are available (MySQL server version 4.1.0 and newer). If your application encounters issues with server-side prepared statements, you can revert to the older client-side emulated prepared statement code that is still presently used for MySQL servers older than 4.1.0 with the following connection property:
useServerPrepStmts=false
You should read this section only if you are interested in helping us test our new code. If you just want to get MySQL Connector/J up and running on your system, you should use a standard binary release distribution.
To install MySQL Connector/J from the development source tree, make sure that you have the following prerequisites:
A Bazaar client, to check out the sources from our Launchpad repository (available from http://bazaar-vcs.org/).
Apache Ant version 1.7 or newer (available from http://ant.apache.org/).
JDK 1.4.2 or later. Although MySQL Connector/J can be be used with older JDKs, to compile it from source you must have at least JDK 1.4.2. If you are building Connector/J 5.1 you will need JDK 1.6.x and an older JDK such as JDK 1.5.x. You will then need to point your JAVA_HOME environment variable at the older installation.
The source code repository for MySQL Connector/J is located on Launchpad at https://code.launchpad.net/connectorj.
To check out and compile a specific branch of MySQL Connector/J, follow these steps:
Check out the latest code from the branch that you want with one of the following commands.
To check out the latest development branch use:
shell> bzr branch lp:connectorj
This creates a connectorj subdirectory
in the current directory that contains the latest sources
for the requested branch.
To check out the latest 5.1 code use:
shell> bzr branch lp:connectorj/5.1
This will create a 5.1 subdirectory in
the current directory containing the latest 5.1 code.
If you are building Connector/J 5.1 make sure that you have both JDK 1.6.x installed and an older JDK such as JDK 1.5.x. This is because Connector/J supports both JDBC 3.0 (which was prior to JDK 1.6.x) and JDBC 4.0. Set your JAVA_HOME environment variable to the path of the older JDK installation.
Change location to either the
connectorj or 5.1
directory, depending on which branch you want to build, to
make it your current working directory. For example:
shell> cd connectorj
If you are building Connector/J 5.1 you need to edit the
build.xml to reflect the location of
your JDK 1.6.x installation. The lines that you need to
change are:
<property name="com.mysql.jdbc.java6.javac" value="C:\jvms\jdk1.6.0\bin\javac.exe" />
<property name="com.mysql.jdbc.java6.rtjar" value="C:\jvms\jdk1.6.0\jre\lib\rt.jar" />
Alternatively, you can set the value of these property names
through the Ant -D option.
Issue the following command to compile the driver and create
a .jar file suitable for installation:
shell> ant dist
This creates a build directory in the
current directory, where all build output will go. A
directory is created in the build
directory that includes the version number of the sources
you are building from. This directory contains the sources,
compiled .class files, and a
.jar file suitable for deployment. For
other possible targets, including ones that will create a
fully packaged distribution, issue the following command:
shell> ant -projecthelp
A newly created .jar file containing
the JDBC driver will be placed in the directory
build/mysql-connector-java-.
[version]
Install the newly created JDBC driver as you would a binary
.jar file that you download from MySQL
by following the instructions in
Section 2.2, “Installing the Driver and Configuring the CLASSPATH”.
A package containing both the binary and source code for Connector/J 5.1 can also be found at the following location: Connector/J 5.1 Download
Examples of using Connector/J are located throughout this document, this section provides a summary and links to these examples.
Example 5.1, “Connector/J: Obtaining a connection from the
DriverManager”
Example 5.2, “Connector/J: Using java.sql.Statement to execute a
SELECT query”
Example 5.6, “Connector/J: Setting CallableStatement input
parameters”
Example 5.7, “Connector/J: Retrieving results and output parameter values”
Example 5.9, “Connector/J: Retrieving AUTO_INCREMENT column values
using SELECT LAST_INSERT_ID()”
Example 5.10, “Connector/J: Retrieving AUTO_INCREMENT column values
in Updatable ResultSets”
Example 5.11, “Connector/J: Using a connection pool with a J2EE application server”
Example 5.12, “Connector/J: Example of transaction with retry logic”
Table of Contents
This section of the manual contains reference material for MySQL Connector/J, some of which is automatically generated during the Connector/J build process.
The name of the class that implements java.sql.Driver in MySQL
Connector/J is com.mysql.jdbc.Driver. The
org.gjt.mm.mysql.Driver class name is also
usable to remain backward-compatible with MM.MySQL. You should
use this class name when registering the driver, or when
otherwise configuring software to use MySQL Connector/J.
The JDBC URL format for MySQL Connector/J is as follows, with items in square brackets ([, ]) being optional:
jdbc:mysql://[host][,failoverhost...][:port]/[database] » [?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...
If the host name is not specified, it defaults to 127.0.0.1. If the port is not specified, it defaults to 3306, the default port number for MySQL servers.
jdbc:mysql://[host:port],[host:port].../[database] » [?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...
If the database is not specified, the connection will be made
with no default database. In this case, you will need to either
call the setCatalog() method on the
Connection instance or fully specify table names using the
database name (that is, SELECT dbname.tablename.colname
FROM dbname.tablename...) in your SQL. Not specifying
the database to use upon connection is generally only useful
when building tools that work with multiple databases, such as
GUI database managers.
JDBC clients should never employ the USE
database statement to specify the desired database,
they should always use the
Connection.setCatalog() method instead.
MySQL Connector/J has fail-over support. This enables the driver
to fail-over to any number of slave hosts and still perform
read-only queries. Fail-over only happens when the connection is
in an autoCommit(true) state, because
fail-over can not happen reliably when a transaction is in
progress. Most application servers and connection pools set
autoCommit to true at the
end of every transaction/connection use.
The fail-over functionality has the following behavior:
If the URL property autoReconnect is false: Failover only happens at connection initialization, and failback occurs when the driver determines that the first host has become available again.
If the URL property autoReconnect is
true: Failover happens when the driver determines that the
connection has failed (before every
query), and falls back to the first host when it determines
that the host has become available again (after
queriesBeforeRetryMaster queries have
been issued).
In either case, whenever you are connected to a "failed-over" server, the connection will be set to read-only state, so queries that would modify data will have exceptions thrown (the query will never be processed by the MySQL server).
Configuration properties define how Connector/J will make a connection to a MySQL server. Unless otherwise noted, properties can be set for a DataSource object or for a Connection object.
Configuration Properties can be set in one of the following ways:
Using the set*() methods on MySQL implementations of java.sql.DataSource (which is the preferred method when using implementations of java.sql.DataSource):
com.mysql.jdbc.jdbc2.optional.MysqlDataSource
com.mysql.jdbc.jdbc2.optional.MysqlConnectionPoolDataSource
As a key/value pair in the java.util.Properties instance
passed to DriverManager.getConnection()
or Driver.connect()
As a JDBC URL parameter in the URL given to
java.sql.DriverManager.getConnection(),
java.sql.Driver.connect() or the MySQL
implementations of the
javax.sql.DataSource
setURL() method.
If the mechanism you use to configure a JDBC URL is XML-based, you will need to use the XML character literal & to separate configuration parameters, as the ampersand is a reserved character for XML.
The properties are listed in the following tables.
Connection/Authentication.
| Property Name | Definition | Default Value | Since Version |
| user | The user to connect as | all versions | |
| password | The password to use when connecting | all versions | |
| socketFactory | The name of the class that the driver should use for creating socket connections to the server. This class must implement the interface 'com.mysql.jdbc.SocketFactory' and have public no-args constructor. | com.mysql.jdbc.StandardSocketFactory | 3.0.3 |
| connectTimeout | Timeout for socket connect (in milliseconds), with 0 being no timeout. Only works on JDK-1.4 or newer. Defaults to '0'. | 0 | 3.0.1 |
| socketTimeout | Timeout on network socket operations (0, the default means no timeout). | 0 | 3.0.1 |
| connectionLifecycleInterceptors | A comma-delimited list of classes that implement "com.mysql.jdbc.ConnectionLifecycleInterceptor" that should notified of connection lifecycle events (creation, destruction, commit, rollback, setCatalog and setAutoCommit) and potentially alter the execution of these commands. ConnectionLifecycleInterceptors are "stackable", more than one interceptor may be specified via the configuration property as a comma-delimited list, with the interceptors executed in order from left to right. | 5.1.4 | |
| useConfigs | Load the comma-delimited list of configuration properties before parsing the URL or applying user-specified properties. These configurations are explained in the 'Configurations' of the documentation. | 3.1.5 | |
| interactiveClient | Set the CLIENT_INTERACTIVE flag, which tells MySQL to timeout connections based on INTERACTIVE_TIMEOUT instead of WAIT_TIMEOUT | false | 3.1.0 |
| localSocketAddress | Hostname or IP address given to explicitly configure the interface that the driver will bind the client side of the TCP/IP connection to when connecting. | 5.0.5 | |
| propertiesTransform | An implementation of com.mysql.jdbc.ConnectionPropertiesTransform that the driver will use to modify URL properties passed to the driver before attempting a connection | 3.1.4 | |
| useCompression | Use zlib compression when communicating with the server (true/false)? Defaults to 'false'. | false | 3.0.17 |
Networking.
| Property Name | Definition | Default Value | Since Version |
| maxAllowedPacket | Maximum allowed packet size to send to server. If not set, the value of system variable 'max_allowed_packet' will be used to initialize this upon connecting. This value will not take effect if set larger than the value of 'max_allowed_packet'. | -1 | 5.1.8 |
| tcpKeepAlive | If connecting using TCP/IP, should the driver set SO_KEEPALIVE? | true | 5.0.7 |
| tcpNoDelay | If connecting using TCP/IP, should the driver set SO_TCP_NODELAY (disabling the Nagle Algorithm)? | true | 5.0.7 |
| tcpRcvBuf | If connecting using TCP/IP, should the driver set SO_RCV_BUF to the given value? The default value of '0', means use the platform default value for this property) | 0 | 5.0.7 |
| tcpSndBuf | If connecting using TCP/IP, should the driver set SO_SND_BUF to the given value? The default value of '0', means use the platform default value for this property) | 0 | 5.0.7 |
| tcpTrafficClass | If connecting using TCP/IP, should the driver set traffic class or type-of-service fields ?See the documentation for java.net.Socket.setTrafficClass() for more information. | 0 | 5.0.7 |
High Availability and Clustering.
| Property Name | Definition | Default Value | Since Version |
| autoReconnect | Should the driver try to re-establish stale and/or dead connections? If enabled the driver will throw an exception for a queries issued on a stale or dead connection, which belong to the current transaction, but will attempt reconnect before the next query issued on the connection in a new transaction. The use of this feature is not recommended, because it has side effects related to session state and data consistency when applications don't handle SQLExceptions properly, and is only designed to be used when you are unable to configure your application to handle SQLExceptions resulting from dead and stale connections properly. Alternatively, investigate setting the MySQL server variable "wait_timeout" to some high value rather than the default of 8 hours. | false | 1.1 |
| autoReconnectForPools | Use a reconnection strategy appropriate for connection pools (defaults to 'false') | false | 3.1.3 |
| failOverReadOnly | When failing over in autoReconnect mode, should the connection be set to 'read-only'? | true | 3.0.12 |
| maxReconnects | Maximum number of reconnects to attempt if autoReconnect is true, default is '3'. | 3 | 1.1 |
| reconnectAtTxEnd | If autoReconnect is set to true, should the driver attempt reconnections at the end of every transaction? | false | 3.0.10 |
| retriesAllDown | When using loadbalancing, the number of times the driver should cycle through available hosts, attempting to connect. Between cycles, the driver will pause for 250ms if no servers are available. | 120 | 5.1.6 |
| initialTimeout | If autoReconnect is enabled, the initial time to wait between re-connect attempts (in seconds, defaults to '2'). | 2 | 1.1 |
| roundRobinLoadBalance | When autoReconnect is enabled, and failoverReadonly is false, should we pick hosts to connect to on a round-robin basis? | false | 3.1.2 |
| queriesBeforeRetryMaster | Number of queries to issue before falling back to master when failed over (when using multi-host failover). Whichever condition is met first, 'queriesBeforeRetryMaster' or 'secondsBeforeRetryMaster' will cause an attempt to be made to reconnect to the master. Defaults to 50. | 50 | 3.0.2 |
| secondsBeforeRetryMaster | How long should the driver wait, when failed over, before attempting | 30 | 3.0.2 |
| selfDestructOnPingMaxOperations | =If set to a non-zero value, the driver will report close the connection and report failure when Connection.ping() or Connection.isValid(int) is called if the connnection's count of commands sent to the server exceeds this value. | 0 | 5.1.6 |
| selfDestructOnPingSecondsLifetime | If set to a non-zero value, the driver will report close the connection and report failure when Connection.ping() or Connection.isValid(int) is called if the connnection's lifetime exceeds this value. | 0 | 5.1.6 |
| resourceId | A globally unique name that identifies the resource that this datasource or connection is connected to, used for XAResource.isSameRM() when the driver can't determine this value based on hostnames used in the URL | 5.0.1 |
Security.
| Property Name | Definition | Default Value | Since Version |
| allowMultiQueries | Allow the use of ';' to delimit multiple queries during one statement (true/false), defaults to 'false' | false | 3.1.1 |
| useSSL | Use SSL when communicating with the server (true/false), defaults to 'false' | false | 3.0.2 |
| requireSSL | Require SSL connection if useSSL=true? (defaults to 'false'). | false | 3.1.0 |
| verifyServerCertificate | If "useSSL" is set to "true", should the driver verify the server's certificate? When using this feature, the keystore parameters should be specified by the "clientCertificateKeyStore*" properties, rather than system properties. | true | 5.1.6 |
| clientCertificateKeyStoreUrl | URL to the client certificate KeyStore (if not specified, use defaults) | 5.1.0 | |
| clientCertificateKeyStoreType | KeyStore type for client certificates (NULL or empty means use the default, which is "JKS". Standard keystore types supported by the JVM are "JKS" and "PKCS12", your environment may have more available depending on what security products are installed and available to the JVM. | JKS | 5.1.0 |
| clientCertificateKeyStorePassword | Password for the client certificates KeyStore | 5.1.0 | |
| trustCertificateKeyStoreUrl | URL to the trusted root certificate KeyStore (if not specified, use defaults) | 5.1.0 | |
| trustCertificateKeyStoreType | KeyStore type for trusted root certificates (NULL or empty means use the default, which is "JKS". Standard keystore types supported by the JVM are "JKS" and "PKCS12", your environment may have more available depending on what security products are installed and available to the JVM. | JKS | 5.1.0 |
| trustCertificateKeyStorePassword | Password for the trusted root certificates KeyStore | 5.1.0 | |
| allowLoadLocalInfile | Should the driver allow use of 'LOAD DATA LOCAL INFILE...' (defaults to 'true'). | true | 3.0.3 |
| allowUrlInLocalInfile | Should the driver allow URLs in 'LOAD DATA LOCAL INFILE' statements? | false | 3.1.4 |
| paranoid | Take measures to prevent exposure sensitive information in error messages and clear data structures holding sensitive data when possible? (defaults to 'false') | false | 3.0.1 |
| passwordCharacterEncoding | What character encoding is used for passwords? Leaving this set to the default value (null), uses the platform character set, which works for ISO8859_1 (i.e. "latin1") passwords. For passwords in other character encodings, the encoding will have to be specified with this property, as it's not possible for the driver to auto-detect this. | 5.1.7 |
Performance Extensions.
| Property Name | Definition | Default Value | Since Version |
| callableStmtCacheSize | If 'cacheCallableStmts' is enabled, how many callable statements should be cached? | 100 | 3.1.2 |
| metadataCacheSize | The number of queries to cache ResultSetMetadata for if cacheResultSetMetaData is set to 'true' (default 50) | 50 | 3.1.1 |
| useLocalSessionState | Should the driver refer to the internal values of autocommit and transaction isolation that are set by Connection.setAutoCommit() and Connection.setTransactionIsolation() and transaction state as maintained by the protocol, rather than querying the database or blindly sending commands to the database for commit() or rollback() method calls? | false | 3.1.7 |
| useLocalTransactionState | Should the driver use the in-transaction state provided by the MySQL protocol to determine if a commit() or rollback() should actually be sent to the database? | false | 5.1.7 |
| prepStmtCacheSize | If prepared statement caching is enabled, how many prepared statements should be cached? | 25 | 3.0.10 |
| prepStmtCacheSqlLimit | If prepared statement caching is enabled, what's the largest SQL the driver will cache the parsing for? | 256 | 3.0.10 |
| alwaysSendSetIsolation | Should the driver always communicate with the database when Connection.setTransactionIsolation() is called? If set to false, the driver will only communicate with the database when the requested transaction isolation is different than the whichever is newer, the last value that was set via Connection.setTransactionIsolation(), or the value that was read from the server when the connection was established. Note that useLocalSessionState=true will force the same behavior as alwaysSendSetIsolation=false, regardless of how alwaysSendSetIsolation is set. | true | 3.1.7 |
| maintainTimeStats | Should the driver maintain various internal timers to enable idle time calculations as well as more verbose error messages when the connection to the server fails? Setting this property to false removes at least two calls to System.getCurrentTimeMillis() per query. | true | 3.1.9 |
| useCursorFetch | If connected to MySQL > 5.0.2, and setFetchSize() > 0 on a statement, should that statement use cursor-based fetching to retrieve rows? | false | 5.0.0 |
| blobSendChunkSize | Chunk to use when sending BLOB/CLOBs via ServerPreparedStatements | 1048576 | 3.1.9 |
| cacheCallableStmts | Should the driver cache the parsing stage of CallableStatements | false | 3.1.2 |
| cachePrepStmts | Should the driver cache the parsing stage of PreparedStatements of client-side prepared statements, the "check" for suitability of server-side prepared and server-side prepared statements themselves? | false | 3.0.10 |
| cacheResultSetMetadata | Should the driver cache ResultSetMetaData for Statements and PreparedStatements? (Req. JDK-1.4+, true/false, default 'false') | false | 3.1.1 |
| cacheServerConfiguration | Should the driver cache the results of 'SHOW VARIABLES' and 'SHOW COLLATION' on a per-URL basis? | false | 3.1.5 |
| defaultFetchSize | The driver will call setFetchSize(n) with this value on all newly-created Statements | 0 | 3.1.9 |
| dontTrackOpenResources | The JDBC specification requires the driver to automatically track and close resources, however if your application doesn't do a good job of explicitly calling close() on statements or result sets, this can cause memory leakage. Setting this property to true relaxes this constraint, and can be more memory efficient for some applications. | false | 3.1.7 |
| dynamicCalendars | Should the driver retrieve the default calendar when required, or cache it per connection/session? | false | 3.1.5 |
| elideSetAutoCommits | If using MySQL-4.1 or newer, should the driver only issue 'set autocommit=n' queries when the server's state doesn't match the requested state by Connection.setAutoCommit(boolean)? | false | 3.1.3 |
| enableQueryTimeouts | When enabled, query timeouts set via Statement.setQueryTimeout() use a shared java.util.Timer instance for scheduling. Even if the timeout doesn't expire before the query is processed, there will be memory used by the TimerTask for the given timeout which won't be reclaimed until the time the timeout would have expired if it hadn't been cancelled by the driver. High-load environments might want to consider disabling this functionality. | true | 5.0.6 |
| holdResultsOpenOverStatementClose | Should the driver close result sets on Statement.close() as required by the JDBC specification? | false | 3.1.7 |
| largeRowSizeThreshold | What size result set row should the JDBC driver consider "large", and thus use a more memory-efficient way of representing the row internally? | 2048 | 5.1.1 |
| loadBalanceStrategy | If using a load-balanced connection to connect to SQL nodes in a MySQL Cluster/NDB configuration (by using the URL prefix "jdbc:mysql:loadbalance://"), which load balancing algorithm should the driver use: (1) "random" - the driver will pick a random host for each request. This tends to work better than round-robin, as the randomness will somewhat account for spreading loads where requests vary in response time, while round-robin can sometimes lead to overloaded nodes if there are variations in response times across the workload. (2) "bestResponseTime" - the driver will route the request to the host that had the best response time for the previous transaction. | random | 5.0.6 |
| locatorFetchBufferSize | If 'emulateLocators' is configured to 'true', what size buffer should be used when fetching BLOB data for getBinaryInputStream? | 1048576 | 3.2.1 |
| rewriteBatchedStatements | Should the driver use multiqueries (irregardless of the setting of "allowMultiQueries") as well as rewriting of prepared statements for INSERT into multi-value inserts when executeBatch() is called? Notice that this has the potential for SQL injection if using plain java.sql.Statements and your code doesn't sanitize input correctly. Notice that for prepared statements, server-side prepared statements can not currently take advantage of this rewrite option, and that if you don't specify stream lengths when using PreparedStatement.set*Stream(), the driver won't be able to determine the optimum number of parameters per batch and you might receive an error from the driver that the resultant packet is too large. Statement.getGeneratedKeys() for these rewritten statements only works when the entire batch includes INSERT statements. | false | 3.1.13 |
| useDirectRowUnpack | Use newer result set row unpacking code that skips a copy from network buffers to a MySQL packet instance and instead reads directly into the result set row data buffers. | true | 5.1.1 |
| useDynamicCharsetInfo | Should the driver use a per-connection cache of character set information queried from the server when necessary, or use a built-in static mapping that is more efficient, but isn't aware of custom character sets or character sets implemented after the release of the JDBC driver? | true | 5.0.6 |
| useFastDateParsing | Use internal String->Date/Time/Timestamp conversion routines to avoid excessive object creation? | true | 5.0.5 |
| useFastIntParsing | Use internal String->Integer conversion routines to avoid excessive object creation? | true | 3.1.4 |
| useJvmCharsetConverters | Always use the character encoding routines built into the JVM, rather than using lookup tables for single-byte character sets? | false | 5.0.1 |
| useReadAheadInput | Use newer, optimized non-blocking, buffered input stream when reading from the server? | true | 3.1.5 |
Debugging/Profiling.
| Property Name | Definition | Default Value | Since Version |
| logger | The name of a class that implements "com.mysql.jdbc.log.Log" that will be used to log messages to. (default is "com.mysql.jdbc.log.StandardLogger", which logs to STDERR) | com.mysql.jdbc.log.StandardLogger | 3.1.1 |
| gatherPerfMetrics | Should the driver gather performance metrics, and report them via the configured logger every 'reportMetricsIntervalMillis' milliseconds? | false | 3.1.2 |
| profileSQL | Trace queries and their execution/fetch times to the configured logger (true/false) defaults to 'false' | false | 3.1.0 |
| profileSql | Deprecated, use 'profileSQL' instead. Trace queries and their execution/fetch times on STDERR (true/false) defaults to 'false' | 2.0.14 | |
| reportMetricsIntervalMillis | If 'gatherPerfMetrics' is enabled, how often should they be logged (in ms)? | 30000 | 3.1.2 |
| maxQuerySizeToLog | Controls the maximum length/size of a query that will get logged when profiling or tracing | 2048 | 3.1.3 |
| packetDebugBufferSize | The maximum number of packets to retain when 'enablePacketDebug' is true | 20 | 3.1.3 |
| slowQueryThresholdMillis | If 'logSlowQueries' is enabled, how long should a query (in ms) before it is logged as 'slow'? | 2000 | 3.1.2 |
| slowQueryThresholdNanos | If 'useNanosForElapsedTime' is set to true, and this property is set to a non-zero value, the driver will use this threshold (in nanosecond units) to determine if a query was slow. | 0 | 5.0.7 |
| useUsageAdvisor | Should the driver issue 'usage' warnings advising proper and efficient usage of JDBC and MySQL Connector/J to the log (true/false, defaults to 'false')? | false | 3.1.1 |
| autoGenerateTestcaseScript | Should the driver dump the SQL it is executing, including server-side prepared statements to STDERR? | false | 3.1.9 |
| autoSlowLog | Instead of using slowQueryThreshold* to determine if a query is slow enough to be logged, maintain statistics that allow the driver to determine queries that are outside the 99th percentile? | true | 5.1.4 |
| clientInfoProvider | The name of a class that implements the com.mysql.jdbc.JDBC4ClientInfoProvider interface in order to support JDBC-4.0's Connection.get/setClientInfo() methods | com.mysql.jdbc.JDBC4CommentClientInfoProvider | 5.1.0 |
| dumpMetadataOnColumnNotFound | Should the driver dump the field-level metadata of a result set into the exception message when ResultSet.findColumn() fails? | false | 3.1.13 |
| dumpQueriesOnException | Should the driver dump the contents of the query sent to the server in the message for SQLExceptions? | false | 3.1.3 |
| enablePacketDebug | When enabled, a ring-buffer of 'packetDebugBufferSize' packets will be kept, and dumped when exceptions are thrown in key areas in the driver's code | false | 3.1.3 |
| explainSlowQueries | If 'logSlowQueries' is enabled, should the driver automatically issue an 'EXPLAIN' on the server and send the results to the configured log at a WARN level? | false | 3.1.2 |
| includeInnodbStatusInDeadlockExceptions | Include the output of "SHOW ENGINE INNODB STATUS" in exception messages when deadlock exceptions are detected? | false | 5.0.7 |
| includeThreadDumpInDeadlockExceptions | Include a current Java thread dump in exception messages when deadlock exceptions are detected? | false | 5.1.15 |
| includeThreadNamesAsStatementComment | Include the name of the current thread as a comment visible in "SHOW PROCESSLIST", or in Innodb deadlock dumps, useful in correlation with "includeInnodbStatusInDeadlockExceptions=true" and "includeThreadDumpInDeadlockExceptions=true". | false | 5.1.15 |
| logSlowQueries | Should queries that take longer than 'slowQueryThresholdMillis' be logged? | false | 3.1.2 |
| logXaCommands | Should the driver log XA commands sent by MysqlXaConnection to the server, at the DEBUG level of logging? | false | 5.0.5 |
| profilerEventHandler | Name of a class that implements the interface com.mysql.jdbc.profiler.ProfilerEventHandler that will be used to handle profiling/tracing events. | com.mysql.jdbc.profiler.LoggingProfilerEventHandler | 5.1.6 |
| resultSetSizeThreshold | If the usage advisor is enabled, how many rows should a result set contain before the driver warns that it is suspiciously large? | 100 | 5.0.5 |
| traceProtocol | Should trace-level network protocol be logged? | false | 3.1.2 |
| useNanosForElapsedTime | For profiling/debugging functionality that measures elapsed time, should the driver try to use nanoseconds resolution if available (JDK >= 1.5)? | false | 5.0.7 |
Miscellaneous.
| Property Name | Definition | Default Value | Since Version |
| useUnicode | Should the driver use Unicode character encodings when handling strings? Should only be used when the driver can't determine the character set mapping, or you are trying to 'force' the driver to use a character set that MySQL either doesn't natively support (such as UTF-8), true/false, defaults to 'true' | true | 1.1g |
| characterEncoding | If 'useUnicode' is set to true, what character encoding should the driver use when dealing with strings? (defaults is to 'autodetect') | 1.1g | |
| characterSetResults | Character set to tell the server to return results as. | 3.0.13 | |
| connectionCollation | If set, tells the server to use this collation via 'set collation_connection' | 3.0.13 | |
| useBlobToStoreUTF8OutsideBMP | Tells the driver to treat [MEDIUM/LONG]BLOB columns as [LONG]VARCHAR columns holding text encoded in UTF-8 that has characters outside the BMP (4-byte encodings), which MySQL server can't handle natively. | false | 5.1.3 |
| utf8OutsideBmpExcludedColumnNamePattern | When "useBlobToStoreUTF8OutsideBMP" is set to "true", column names matching the given regex will still be treated as BLOBs unless they match the regex specified for "utf8OutsideBmpIncludedColumnNamePattern". The regex must follow the patterns used for the java.util.regex package. | 5.1.3 | |
| utf8OutsideBmpIncludedColumnNamePattern | Used to specify exclusion rules to "utf8OutsideBmpExcludedColumnNamePattern". The regex must follow the patterns used for the java.util.regex package. | 5.1.3 | |
| loadBalanceEnableJMX | Enables JMX-based management of load-balanced connection groups, including live addition/removal of hosts from load-balancing pool. | false | 5.1.13 |
| sessionVariables | A comma-separated list of name/value pairs to be sent as SET SESSION ... to the server when the driver connects. | 3.1.8 | |
| useColumnNamesInFindColumn | Prior to JDBC-4.0, the JDBC specification had a bug related to what could be given as a "column name" to ResultSet methods like findColumn(), or getters that took a String property. JDBC-4.0 clarified "column name" to mean the label, as given in an "AS" clause and returned by ResultSetMetaData.getColumnLabel(), and if no AS clause, the column name. Setting this property to "true" will give behavior that is congruent to JDBC-3.0 and earlier versions of the JDBC specification, but which because of the specification bug could give unexpected results. This property is preferred over "useOldAliasMetadataBehavior" unless you need the specific behavior that it provides with respect to ResultSetMetadata. | false | 5.1.7 |
| allowNanAndInf | Should the driver allow NaN or +/- INF values in PreparedStatement.setDouble()? | false | 3.1.5 |
| autoClosePStmtStreams | Should the driver automatically call .close() on streams/readers passed as arguments via set*() methods? | false | 3.1.12 |
| autoDeserialize | Should the driver automatically detect and de-serialize objects stored in BLOB fields? | false | 3.1.5 |
| blobsAreStrings | Should the driver always treat BLOBs as Strings - specifically to work around dubious metadata returned by the server for GROUP BY clauses? | false | 5.0.8 |
| capitalizeTypeNames | Capitalize type names in DatabaseMetaData? (usually only useful when using WebObjects, true/false, defaults to 'false') | true | 2.0.7 |
| clobCharacterEncoding | The character encoding to use for sending and retrieving TEXT, MEDIUMTEXT and LONGTEXT values instead of the configured connection characterEncoding | 5.0.0 | |
| clobberStreamingResults | This will cause a 'streaming' ResultSet to be automatically closed, and any outstanding data still streaming from the server to be discarded if another query is executed before all the data has been read from the server. | false | 3.0.9 |
| compensateOnDuplicateKeyUpdateCounts | Should the driver compensate for the update counts of "ON DUPLICATE KEY" INSERT statements (2 = 1, 0 = 1) when using prepared statements? | false | 5.1.7 |
| continueBatchOnError | Should the driver continue processing batch commands if one statement fails. The JDBC spec allows either way (defaults to 'true'). | true | 3.0.3 |
| createDatabaseIfNotExist | Creates the database given in the URL if it doesn't yet exist. Assumes the configured user has permissions to create databases. | false | 3.1.9 |
| emptyStringsConvertToZero | Should the driver allow conversions from empty string fields to numeric values of '0'? | true | 3.1.8 |
| emulateLocators | Should the driver emulate java.sql.Blobs with locators? With this feature enabled, the driver will delay loading the actual Blob data until the one of the retrieval methods (getInputStream(), getBytes(), and so forth) on the blob data stream has been accessed. For this to work, you must use a column alias with the value of the column to the actual name of the Blob. The feature also has the following restrictions: The SELECT that created the result set must reference only one table, the table must have a primary key; the SELECT must alias the original blob column name, specified as a string, to an alternate name; the SELECT must cover all columns that make up the primary key. | false | 3.1.0 |
| emulateUnsupportedPstmts | Should the driver detect prepared statements that are not supported by the server, and replace them with client-side emulated versions? | true | 3.1.7 |
| exceptionInterceptors | Comma-delimited list of classes that implement com.mysql.jdbc.ExceptionInterceptor. These classes will be instantiated one per Connection instance, and all SQLExceptions thrown by the driver will be allowed to be intercepted by these interceptors, in a chained fashion, with the first class listed as the head of the chain. | 5.1.8 | |
| functionsNeverReturnBlobs | Should the driver always treat data from functions returning BLOBs as Strings - specifically to work around dubious metadata returned by the server for GROUP BY clauses? | false | 5.0.8 |
| generateSimpleParameterMetadata | Should the driver generate simplified parameter metadata for PreparedStatements when no metadata is available either because the server couldn't support preparing the statement, or server-side prepared statements are disabled? | false | 5.0.5 |
| ignoreNonTxTables | Ignore non-transactional table warning for rollback? (defaults to 'false'). | false | 3.0.9 |
| jdbcCompliantTruncation | Should the driver throw java.sql.DataTruncation exceptions when data is truncated as is required by the JDBC specification when connected to a server that supports warnings (MySQL 4.1.0 and newer)? This property has no effect if the server sql-mode includes STRICT_TRANS_TABLES. | true | 3.1.2 |
| loadBalanceAutoCommitStatementRegex | When load-balancing is enabled for auto-commit statements (via loadBalanceAutoCommitStatementThreshold), the statement counter will only increment when the SQL matches the regular expression. By default, every statement issued matches. | 5.1.15 | |
| loadBalanceAutoCommitStatementThreshold | When auto-commit is enabled, the number of statements which should be executed before triggering load-balancing to rebalance. Default value of 0 causes load-balanced connections to only rebalance when exceptions are encountered, or auto-commit is disabled and transactions are explicitly committed or rolled back. | 0 | 5.1.15 |
| loadBalanceBlacklistTimeout | Time in milliseconds between checks of servers which are unavailable. | 0 | 5.1.0 |
| loadBalanceConnectionGroup | Logical group of load-balanced connections within a classloader, used to manage different groups independently. If not specified, live management of load-balanced connections is disabled. | 5.1.13 | |
| loadBalanceExceptionChecker | Fully-qualified class name of custom exception checker. The class must implement com.mysql.jdbc.LoadBalanceExceptionChecker interface, and is used to inspect SQLExceptions and determine whether they should trigger fail-over to another host in a load-balanced deployment. | com.mysql.jdbc.StandardLoadBalanceExceptionChecker | 5.1.13 |
| loadBalancePingTimeout | Time in milliseconds to wait for ping response from each of load-balanced physical connections when using load-balanced Connection. | 0 | 5.1.13 |
| loadBalanceSQLExceptionSubclassFailover | Comma-delimited list of classes/interfaces used by default load-balanced exception checker to determine whether a given SQLException should trigger failover. The comparison is done using Class.isInstance(SQLException) using the thrown SQLException. | 5.1.13 | |
| loadBalanceSQLStateFailover | Comma-delimited list of SQLState codes used by default load-balanced exception checker to determine whether a given SQLException should trigger failover. The SQLState of a given SQLException is evaluated to determine whether it begins with any value in the comma-delimited list. | 5.1.13 | |
| loadBalanceValidateConnectionOnSwapServer | Should the load-balanced Connection explicitly check whether the connection is live when swapping to a new physical connection at commit/rollback? | false | 5.1.13 |
| maxRows | The maximum number of rows to return (0, the default means return all rows). | -1 | all versions |
| netTimeoutForStreamingResults | What value should the driver automatically set the server setting 'net_write_timeout' to when the streaming result sets feature is in use? (value has unit of seconds, the value '0' means the driver will not try and adjust this value) | 600 | 5.1.0 |
| noAccessToProcedureBodies | When determining procedure parameter types for CallableStatements, and the connected user can't access procedure bodies through "SHOW CREATE PROCEDURE" or select on mysql.proc should the driver instead create basic metadata (all parameters reported as IN VARCHARs, but allowing registerOutParameter() to be called on them anyway) instead of throwing an exception? | false | 5.0.3 |
| noDatetimeStringSync | Don't ensure that ResultSet.getDatetimeType().toString().equals(ResultSet.getString()) | false | 3.1.7 |
| noTimezoneConversionForTimeType | Don't convert TIME values using the server timezone if 'useTimezone'='true' | false | 5.0.0 |
| nullCatalogMeansCurrent | When DatabaseMetadataMethods ask for a 'catalog' parameter, does the value null mean use the current catalog? (this is not JDBC-compliant, but follows legacy behavior from earlier versions of the driver) | true | 3.1.8 |
| nullNamePatternMatchesAll | Should DatabaseMetaData methods that accept *pattern parameters treat null the same as '%' (this is not JDBC-compliant, however older versions of the driver accepted this departure from the specification) | true | 3.1.8 |
| overrideSupportsIntegrityEnhancementFacility | Should the driver return "true" for DatabaseMetaData.supportsIntegrityEnhancementFacility() even if the database doesn't support it to workaround applications that require this method to return "true" to signal support of foreign keys, even though the SQL specification states that this facility contains much more than just foreign key support (one such application being OpenOffice)? | false | 3.1.12 |
| padCharsWithSpace | If a result set column has the CHAR type and the value does not fill the amount of characters specified in the DDL for the column, should the driver pad the remaining characters with space (for ANSI compliance)? | false | 5.0.6 |
| pedantic | Follow the JDBC spec to the letter. | false | 3.0.0 |
| pinGlobalTxToPhysicalConnection | When using XAConnections, should the driver ensure that operations on a given XID are always routed to the same physical connection? This allows the XAConnection to support "XA START ... JOIN" after "XA END" has been called | false | 5.0.1 |
| populateInsertRowWithDefaultValues | When using ResultSets that are CONCUR_UPDATABLE, should the driver pre-populate the "insert" row with default values from the DDL for the table used in the query so those values are immediately available for ResultSet accessors? This functionality requires a call to the database for metadata each time a result set of this type is created. If disabled (the default), the default values will be populated by the an internal call to refreshRow() which pulls back default values and/or values changed by triggers. | false | 5.0.5 |
| processEscapeCodesForPrepStmts | Should the driver process escape codes in queries that are prepared? | true | 3.1.12 |
| queryTimeoutKillsConnection | If the timeout given in Statement.setQueryTimeout() expires, should the driver forcibly abort the Connection instead of attempting to abort the query? | false | 5.1.9 |
| relaxAutoCommit | If the version of MySQL the driver connects to does not support transactions, still allow calls to commit(), rollback() and setAutoCommit() (true/false, defaults to 'false')? | false | 2.0.13 |
| retainStatementAfterResultSetClose | Should the driver retain the Statement reference in a ResultSet after ResultSet.close() has been called. This is not JDBC-compliant after JDBC-4.0. | false | 3.1.11 |
| rollbackOnPooledClose | Should the driver issue a rollback() when the logical connection in a pool is closed? | true | 3.0.15 |
| runningCTS13 | Enables workarounds for bugs in Sun's JDBC compliance testsuite version 1.3 | false | 3.1.7 |
| serverTimezone | Override detection/mapping of timezone. Used when timezone from server doesn't map to Java timezone | 3.0.2 | |
| statementInterceptors | A comma-delimited list of classes that implement "com.mysql.jdbc.StatementInterceptor" that should be placed "in between" query execution to influence the results. StatementInterceptors are "chainable", the results returned by the "current" interceptor will be passed on to the next in in the chain, from left-to-right order, as specified in this property. | 5.1.1 | |
| strictFloatingPoint | Used only in older versions of compliance test | false | 3.0.0 |
| strictUpdates | Should the driver do strict checking (all primary keys selected) of updatable result sets (true, false, defaults to 'true')? | true | 3.0.4 |
| tinyInt1isBit | Should the driver treat the datatype TINYINT(1) as the BIT type (because the server silently converts BIT -> TINYINT(1) when creating tables)? | true | 3.0.16 |
| transformedBitIsBoolean | If the driver converts TINYINT(1) to a different type, should it use BOOLEAN instead of BIT for future compatibility with MySQL-5.0, as MySQL-5.0 has a BIT type? | false | 3.1.9 |
| treatUtilDateAsTimestamp | Should the driver treat java.util.Date as a TIMESTAMP for the purposes of PreparedStatement.setObject()? | true | 5.0.5 |
| ultraDevHack | Create PreparedStatements for prepareCall() when required, because UltraDev is broken and issues a prepareCall() for _all_ statements? (true/false, defaults to 'false') | false | 2.0.3 |
| useAffectedRows | Don't set the CLIENT_FOUND_ROWS flag when connecting to the server (not JDBC-compliant, will break most applications that rely on "found" rows vs. "affected rows" for DML statements), but does cause "correct" update counts from "INSERT ... ON DUPLICATE KEY UPDATE" statements to be returned by the server. | false | 5.1.7 |
| useGmtMillisForDatetimes | Convert between session timezone and GMT before creating Date and Timestamp instances (value of "false" is legacy behavior, "true" leads to more JDBC-compliant behavior. | false | 3.1.12 |
| useHostsInPrivileges | Add '@hostname' to users in DatabaseMetaData.getColumn/TablePrivileges() (true/false), defaults to 'true'. | true | 3.0.2 |
| useInformationSchema | When connected to MySQL-5.0.7 or newer, should the driver use the INFORMATION_SCHEMA to derive information used by DatabaseMetaData? | false | 5.0.0 |
| useJDBCCompliantTimezoneShift | Should the driver use JDBC-compliant rules when converting TIME/TIMESTAMP/DATETIME values' timezone information for those JDBC arguments which take a java.util.Calendar argument? (Notice that this option is exclusive of the "useTimezone=true" configuration option.) | false | 5.0.0 |
| useLegacyDatetimeCode | Use code for DATE/TIME/DATETIME/TIMESTAMP handling in result sets and statements that consistently handles timezone conversions from client to server and back again, or use the legacy code for these datatypes that has been in the driver for backwards-compatibility? | true | 5.1.6 |
| useOldAliasMetadataBehavior | Should the driver use the legacy behavior for "AS" clauses on columns and tables, and only return aliases (if any) for ResultSetMetaData.getColumnName() or ResultSetMetaData.getTableName() rather than the original column/table name? In 5.0.x, the default value was true. | false | 5.0.4 |
| useOldUTF8Behavior | Use the UTF-8 behavior the driver did when communicating with 4.0 and older servers | false | 3.1.6 |
| useOnlyServerErrorMessages | Don't prepend 'standard' SQLState error messages to error messages returned by the server. | true | 3.0.15 |
| useSSPSCompatibleTimezoneShift | If migrating from an environment that was using server-side prepared statements, and the configuration property "useJDBCCompliantTimeZoneShift" set to "true", use compatible behavior when not using server-side prepared statements when sending TIMESTAMP values to the MySQL server. | false | 5.0.5 |
| useServerPrepStmts | Use server-side prepared statements if the server supports them? | false | 3.1.0 |
| useSqlStateCodes | Use SQL Standard state codes instead of 'legacy' X/Open/SQL state codes (true/false), default is 'true' | true | 3.1.3 |
| useStreamLengthsInPrepStmts | Honor stream length parameter in PreparedStatement/ResultSet.setXXXStream() method calls (true/false, defaults to 'true')? | true | 3.0.2 |
| useTimezone | Convert time/date types between client and server timezones (true/false, defaults to 'false')? | false | 3.0.2 |
| useUnbufferedInput | Don't use BufferedInputStream for reading data from the server | true | 3.0.11 |
| yearIsDateType | Should the JDBC driver treat the MySQL type "YEAR" as a java.sql.Date, or as a SHORT? | true | 3.1.9 |
| zeroDateTimeBehavior | What should happen when the driver encounters DATETIME values that are composed entirely of zeros (used by MySQL to represent invalid dates)? Valid values are "exception", "round" and "convertToNull". | exception | 3.1.4 |
Connector/J also supports access to MySQL using named pipes on
Windows NT/2000/XP using the
NamedPipeSocketFactory as a plugin-socket
factory using the socketFactory property.
If you do not use a namedPipePath property,
the default of '\\.\pipe\MySQL' will be used. If you use the
NamedPipeSocketFactory, the host name and
port number values in the JDBC url will be ignored. You can
enable this feature using:
socketFactory=com.mysql.jdbc.NamedPipeSocketFactory
Named pipes only work when connecting to a MySQL server on the same physical machine as the one the JDBC driver is being used on. In simple performance tests, it appears that named pipe access is between 30%-50% faster than the standard TCP/IP access. However, this varies per system, and named pipes are slower than TCP/IP in many Windows configurations.
You can create your own socket factories by following the
example code in
com.mysql.jdbc.NamedPipeSocketFactory, or
com.mysql.jdbc.StandardSocketFactory.
MySQL Connector/J passes all of the tests in the publicly available version of Sun's JDBC compliance test suite. However, in many places the JDBC specification is vague about how certain functionality should be implemented, or the specification enables leeway in implementation.
This section gives details on a interface-by-interface level about how certain implementation decisions may affect how you use MySQL Connector/J.
Blob
Starting with Connector/J version 3.1.0, you can emulate
Blobs with locators by adding the property
'emulateLocators=true' to your JDBC URL. Using this method,
the driver will delay loading the actual Blob data until you
retrieve the other data and then use retrieval methods
(getInputStream(),
getBytes(), and so forth) on the blob
data stream.
For this to work, you must use a column alias with the value of the column to the actual name of the Blob, for example:
SELECT id, 'data' as blob_data from blobtable
For this to work, you must also follow these rules:
The Blob implementation does not allow in-place modification
(they are copies, as reported by the
DatabaseMetaData.locatorsUpdateCopies()
method). Because of this, you should use the corresponding
PreparedStatement.setBlob() or
ResultSet.updateBlob() (in the case of
updatable result sets) methods to save changes back to the
database.
CallableStatement
Starting with Connector/J 3.1.1, stored procedures are
supported when connecting to MySQL version 5.0 or newer
using the CallableStatement
interface. Currently, the
getParameterMetaData() method of
CallableStatement is not supported.
Clob
The Clob implementation does not allow in-place modification
(they are copies, as reported by the
DatabaseMetaData.locatorsUpdateCopies()
method). Because of this, you should use the
PreparedStatement.setClob() method to
save changes back to the database. The JDBC API does not
have a ResultSet.updateClob() method.
Connection
Unlike older versions of MM.MySQL the
isClosed() method does not ping the
server to determine if it is available. In accordance with
the JDBC specification, it only returns true if
closed() has been called on the
connection. If you need to determine if the connection is
still valid, you should issue a simple query, such as
SELECT 1. The driver will throw an
exception if the connection is no longer valid.
DatabaseMetaData
Foreign Key information
(getImportedKeys()/getExportedKeys()
and getCrossReference()) is only
available from InnoDB tables. However, the driver uses
SHOW CREATE TABLE to retrieve
this information, so when other storage engines support
foreign keys, the driver will transparently support them as
well.
PreparedStatement
PreparedStatements are implemented by the driver, as MySQL
does not have a prepared statement feature. Because of this,
the driver does not implement
getParameterMetaData() or
getMetaData() as it would require the
driver to have a complete SQL parser in the client.
Starting with version 3.1.0 MySQL Connector/J, server-side prepared statements and binary-encoded result sets are used when the server supports them.
Take care when using a server-side prepared statement with
large parameters that are
set using setBinaryStream(),
setAsciiStream(),
setUnicodeStream(),
setBlob(), or
setClob(). If you want to re-execute
the statement with any large parameter changed to a nonlarge
parameter, it is necessary to call
clearParameters() and set all
parameters again. The reason for this is as follows:
During both server-side prepared statements and
client-side emulation, large data is exchanged only when
PreparedStatement.execute() is
called.
Once that has been done, the stream used to read the data on the client side is closed (as per the JDBC spec), and cannot be read from again.
If a parameter changes from large to nonlarge, the
driver must reset the server-side state of the prepared
statement to allow the parameter that is being changed
to take the place of the prior large value. This removes
all of the large data that has already been sent to the
server, thus requiring the data to be re-sent, using the
setBinaryStream(),
setAsciiStream(),
setUnicodeStream(),
setBlob() or
setClob() method.
Consequently, if you want to change the type of a parameter
to a nonlarge one, you must call
clearParameters() and set all
parameters of the prepared statement again before it can be
re-executed.
ResultSet
By default, ResultSets are completely retrieved and stored in memory. In most cases this is the most efficient way to operate, and due to the design of the MySQL network protocol is easier to implement. If you are working with ResultSets that have a large number of rows or large values, and can not allocate heap space in your JVM for the memory required, you can tell the driver to stream the results back one row at a time.
To enable this functionality, you need to create a Statement instance in the following manner:
stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
java.sql.ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(Integer.MIN_VALUE);
The combination of a forward-only, read-only result set,
with a fetch size of Integer.MIN_VALUE
serves as a signal to the driver to stream result sets
row-by-row. After this any result sets created with the
statement will be retrieved row-by-row.
There are some caveats with this approach. You will have to read all of the rows in the result set (or close it) before you can issue any other queries on the connection, or an exception will be thrown.
The earliest the locks these statements hold can be released
(whether they be MyISAM table-level locks
or row-level locks in some other storage engine such as
InnoDB) is when the statement completes.
If the statement is within scope of a transaction, then locks are released when the transaction completes (which implies that the statement needs to complete first). As with most other databases, statements are not complete until all the results pending on the statement are read or the active result set for the statement is closed.
Therefore, if using streaming results, you should process them as quickly as possible if you want to maintain concurrent access to the tables referenced by the statement producing the result set.
ResultSetMetaData
The isAutoIncrement() method only works
when using MySQL servers 4.0 and newer.
Statement
When using versions of the JDBC driver earlier than 3.2.1,
and connected to server versions earlier than 5.0.3, the
setFetchSize() method has no effect,
other than to toggle result set streaming as described
above.
Connector/J 5.0.0 and later include support for both
Statement.cancel() and
Statement.setQueryTimeout(). Both require
MySQL 5.0.0 or newer server, and require a separate
connection to issue the
KILL QUERY
statement. In the case of
setQueryTimeout(), the implementation
creates an additional thread to handle the timeout
functionality.
Failures to cancel the statement for
setQueryTimeout() may manifest
themselves as RuntimeException rather
than failing silently, as there is currently no way to
unblock the thread that is executing the query being
cancelled due to timeout expiration and have it throw the
exception instead.
MySQL does not support SQL cursors, and the JDBC driver doesn't emulate them, so "setCursorName()" has no effect.
Connector/J 5.1.3 and later include two additional methods:
setLocalInfileInputStream() sets an
InputStream instance that will be
used to send data to the MySQL server for a
LOAD DATA
LOCAL INFILE statement rather than a
FileInputStream or
URLInputStream that represents the
path given as an argument to the statement.
This stream will be read to completion upon execution of
a LOAD DATA
LOCAL INFILE statement, and will automatically
be closed by the driver, so it needs to be reset before
each call to execute*() that would
cause the MySQL server to request data to fulfill the
request for
LOAD DATA
LOCAL INFILE.
If this value is set to NULL, the
driver will revert to using a
FileInputStream or
URLInputStream as required.
getLocalInfileInputStream() returns
the InputStream instance that will be
used to send data in response to a
LOAD DATA
LOCAL INFILE statement.
This method returns NULL if no such
stream has been set using
setLocalInfileInputStream().
MySQL Connector/J is flexible in the way it handles conversions between MySQL data types and Java data types.
In general, any MySQL data type can be converted to a java.lang.String, and any numeric type can be converted to any of the Java numeric types, although round-off, overflow, or loss of precision may occur.
Starting with Connector/J 3.1.0, the JDBC driver will issue
warnings or throw DataTruncation exceptions as is required by
the JDBC specification unless the connection was configured not
to do so by using the property
jdbcCompliantTruncation and setting it to
false.
The conversions that are always guaranteed to work are listed in the following table:
Connection Properties - Miscellaneous.
| These MySQL Data Types | Can always be converted to these Java types |
|---|---|
CHAR, VARCHAR, BLOB, TEXT, ENUM, and SET | java.lang.String, java.io.InputStream, java.io.Reader,
java.sql.Blob, java.sql.Clob |
FLOAT, REAL, DOUBLE PRECISION, NUMERIC, DECIMAL, TINYINT,
SMALLINT, MEDIUMINT, INTEGER, BIGINT | java.lang.String, java.lang.Short, java.lang.Integer,
java.lang.Long, java.lang.Double,
java.math.BigDecimal |
DATE, TIME, DATETIME, TIMESTAMP | java.lang.String, java.sql.Date, java.sql.Timestamp |
Round-off, overflow or loss of precision may occur if you choose a Java numeric data type that has less precision or capacity than the MySQL data type you are converting to/from.
The ResultSet.getObject() method uses the
type conversions between MySQL and Java types, following the
JDBC specification where appropriate. The value returned by
ResultSetMetaData.GetColumnClassName() is
also shown below. For more information on the
java.sql.Types classes see
Java
2 Platform Types.
MySQL Types to Java Types for ResultSet.getObject().
| MySQL Type Name | Return value of GetColumnClassName | Returned as Java Class |
|---|---|---|
| BIT(1) (new in MySQL-5.0) | BIT | java.lang.Boolean |
| BIT( > 1) (new in MySQL-5.0) | BIT | byte[] |
| TINYINT | TINYINT | java.lang.Boolean if the configuration property
tinyInt1isBit is set to
true (the default) and the
storage size is 1, or
java.lang.Integer if not. |
| BOOL, BOOLEAN | TINYINT | See TINYINT, above as these are aliases for TINYINT(1), currently. |
| SMALLINT[(M)] [UNSIGNED] | SMALLINT [UNSIGNED] | java.lang.Integer (regardless if UNSIGNED or not) |
| MEDIUMINT[(M)] [UNSIGNED] | MEDIUMINT [UNSIGNED] | java.lang.Integer, if UNSIGNED
java.lang.Long (C/J 3.1 and
earlier), or
java.lang.Integer for C/J 5.0
and later |
| INT,INTEGER[(M)] [UNSIGNED] | INTEGER [UNSIGNED] | java.lang.Integer, if UNSIGNED
java.lang.Long |
| BIGINT[(M)] [UNSIGNED] | BIGINT [UNSIGNED] | java.lang.Long, if UNSIGNED
java.math.BigInteger |
| FLOAT[(M,D)] | FLOAT | java.lang.Float |
| DOUBLE[(M,B)] | DOUBLE | java.lang.Double |
| DECIMAL[(M[,D])] | DECIMAL | java.math.BigDecimal |
| DATE | DATE | java.sql.Date |
| DATETIME | DATETIME | java.sql.Timestamp |
| TIMESTAMP[(M)] | TIMESTAMP | java.sql.Timestamp |
| TIME | TIME | java.sql.Time |
| YEAR[(2|4)] | YEAR | If yearIsDateType configuration property is set to
false, then the returned object type is
java.sql.Short. If set to
true (the default) then an object of type
java.sql.Date (with the date
set to January 1st, at midnight). |
| CHAR(M) | CHAR | java.lang.String (unless the character set for
the column is BINARY, then
byte[] is returned. |
| VARCHAR(M) [BINARY] | VARCHAR | java.lang.String (unless the character set for
the column is BINARY, then
byte[] is returned. |
| BINARY(M) | BINARY | byte[] |
| VARBINARY(M) | VARBINARY | byte[] |
| TINYBLOB | TINYBLOB | byte[] |
| TINYTEXT | VARCHAR | java.lang.String |
| BLOB | BLOB | byte[] |
| TEXT | VARCHAR | java.lang.String |
| MEDIUMBLOB | MEDIUMBLOB | byte[] |
| MEDIUMTEXT | VARCHAR | java.lang.String |
| LONGBLOB | LONGBLOB | byte[] |
| LONGTEXT | VARCHAR | java.lang.String |
| ENUM('value1','value2',...) | CHAR | java.lang.String |
| SET('value1','value2',...) | CHAR | java.lang.String |
All strings sent from the JDBC driver to the server are
converted automatically from native Java Unicode form to the
client character encoding, including all queries sent using
Statement.execute(),
Statement.executeUpdate(),
Statement.executeQuery() as well as all
PreparedStatement
and
CallableStatement
parameters with the exclusion of parameters set using
setBytes(),
setBinaryStream(),
setAsciiStream(),
setUnicodeStream() and
setBlob().
Prior to MySQL Server 4.1, Connector/J supported a single
character encoding per connection, which could either be
automatically detected from the server configuration, or could
be configured by the user through the
useUnicode and
characterEncoding properties.
Starting with MySQL Server 4.1, Connector/J supports a single
character encoding between client and server, and any number of
character encodings for data returned by the server to the
client in ResultSets.
The character encoding between client and server is
automatically detected upon connection. The encoding used by the
driver is specified on the server using the
character_set system variable for server
versions older than 4.1.0 and
character_set_server for server
versions 4.1.0 and newer. For more information, see
Server Character Set and Collation.
To override the automatically detected encoding on the client
side, use the characterEncoding property
in the URL used to connect to the server.
When specifying character encodings on the client side, Java-style names should be used. The following table lists Java-style names for MySQL character sets:
MySQL to Java Encoding Name Translations.
| MySQL Character Set Name | Java-Style Character Encoding Name |
|---|---|
| ascii | US-ASCII |
| big5 | Big5 |
| gbk | GBK |
| sjis | SJIS (or Cp932 or MS932 for MySQL Server < 4.1.11) |
| cp932 | Cp932 or MS932 (MySQL Server > 4.1.11) |
| gb2312 | EUC_CN |
| ujis | EUC_JP |
| euckr | EUC_KR |
| latin1 | Cp1252 |
| latin2 | ISO8859_2 |
| greek | ISO8859_7 |
| hebrew | ISO8859_8 |
| cp866 | Cp866 |
| tis620 | TIS620 |
| cp1250 | Cp1250 |
| cp1251 | Cp1251 |
| cp1257 | Cp1257 |
| macroman | MacRoman |
| macce | MacCentralEurope |
| utf8 | UTF-8 |
| ucs2 | UnicodeBig |
Do not issue the query 'set names' with Connector/J, as the driver will not detect that the character set has changed, and will continue to use the character set detected during the initial connection setup.
To allow multiple character sets to be sent from the client, the
UTF-8 encoding should be used, either by configuring
utf8 as the default server character set, or
by configuring the JDBC driver to use UTF-8 through the
characterEncoding property.
SSL in MySQL Connector/J encrypts all data (other than the initial handshake) between the JDBC driver and the server. The performance penalty for enabling SSL is an increase in query processing time between 35% and 50%, depending on the size of the query, and the amount of data it returns.
For SSL Support to work, you must have the following:
A JDK that includes JSSE (Java Secure Sockets Extension), like JDK-1.4.1 or newer. SSL does not currently work with a JDK that you can add JSSE to, like JDK-1.2.x or JDK-1.3.x due to the following JSSE bug: http://developer.java.sun.com/developer/bugParade/bugs/4273544.html
A MySQL server that supports SSL and has been compiled and configured to do so, which is MySQL-4.0.4 or later, see Using SSL for Secure Connections, for more information.
A client certificate (covered later in this section)
The system works through two Java truststore files, one file
contains the certificate information for the server
(truststore in the examples below). The
other file contains the certificate for the client
(keystore in the examples below). All Java
truststore files are password protected by supplying a suitable
password to the keytool when you create the
files. You need the file names and associated passwords to
create an SSL connection.
You will first need to import the MySQL server CA Certificate
into a Java truststore. A sample MySQL server CA Certificate is
located in the SSL subdirectory of the
MySQL source distribution. This is what SSL will use to
determine if you are communicating with a secure MySQL server.
Alternatively, use the CA Certificate that you have generated or
been provided with by your SSL provider.
To use Java's keytool to create a truststore
in the current directory , and import the server's CA
certificate (cacert.pem), you can do the
following (assuming that keytool is in your
path. The keytool should be located in the
bin subdirectory of your JDK or JRE):
shell> keytool -import -alias mysqlServerCACert \
-file cacert.pem -keystore truststoreYou will need to enter the password when prompted for the keystore file. Interaction with keytool will look like this:
Enter keystore password: *********
Owner: EMAILADDRESS=walrus@example.com, CN=Walrus,
O=MySQL AB, L=Orenburg, ST=Some-State, C=RU
Issuer: EMAILADDRESS=walrus@example.com, CN=Walrus,
O=MySQL AB, L=Orenburg, ST=Some-State, C=RU
Serial number: 0
Valid from:
Fri Aug 02 16:55:53 CDT 2002 until: Sat Aug 02 16:55:53 CDT 2003
Certificate fingerprints:
MD5: 61:91:A0:F2:03:07:61:7A:81:38:66:DA:19:C4:8D:AB
SHA1: 25:77:41:05:D5:AD:99:8C:14:8C:CA:68:9C:2F:B8:89:C3:34:4D:6C
Trust this certificate? [no]: yes
Certificate was added to keystoreYou then have two options, you can either import the client certificate that matches the CA certificate you just imported, or you can create a new client certificate.
To import an existing certificate, the certificate should be in DER format. You can use openssl to convert an existing certificate into the new format. For example:
shell> openssl x509 -outform DER -in client-cert.pem -out client.cert
You now need to import the converted certificate into your keystore using keytool:
shell> keytool -import -file client.cert -keystore keystore -alias mysqlClientCertificate
To generate your own client certificate, use
keytool to create a suitable certificate and
add it to the keystore file:
shell> keytool -genkey -keyalg rsa \
-alias mysqlClientCertificate -keystore keystore
Keytool will prompt you for the following information, and
create a keystore named keystore in the
current directory.
You should respond with information that is appropriate for your situation:
Enter keystore password: *********
What is your first and last name?
[Unknown]: Matthews
What is the name of your organizational unit?
[Unknown]: Software Development
What is the name of your organization?
[Unknown]: MySQL AB
What is the name of your City or Locality?
[Unknown]: Flossmoor
What is the name of your State or Province?
[Unknown]: IL
What is the two-letter country code for this unit?
[Unknown]: US
Is <CN=Matthews, OU=Software Development, O=MySQL AB,
L=Flossmoor, ST=IL, C=US> correct?
[no]: y
Enter key password for <mysqlClientCertificate>
(RETURN if same as keystore password):Finally, to get JSSE to use the keystore and truststore that you have generated, you need to set the following system properties when you start your JVM, replacing path_to_keystore_file with the full path to the keystore file you created, path_to_truststore_file with the path to the truststore file you created, and using the appropriate password values for each property. You can do this either on the command line:
-Djavax.net.ssl.keyStore=path_to_keystore_file -Djavax.net.ssl.keyStorePassword=password -Djavax.net.ssl.trustStore=path_to_truststore_file -Djavax.net.ssl.trustStorePassword=password
Or you can set the values directly within the application:
System.setProperty("javax.net.ssl.keyStore","path_to_keystore_file");
System.setProperty("javax.net.ssl.keyStorePassword","password");
System.setProperty("javax.net.ssl.trustStore","path_to_truststore_file");
System.setProperty("javax.net.ssl.trustStorePassword","password");
You will also need to set useSSL to
true in your connection parameters for MySQL
Connector/J, either by adding useSSL=true to
your URL, or by setting the property useSSL
to true in the
java.util.Properties instance you pass to
DriverManager.getConnection().
You can test that SSL is working by turning on JSSE debugging (as detailed below), and look for the following key events:
...
*** ClientHello, v3.1
RandomCookie: GMT: 1018531834 bytes = { 199, 148, 180, 215, 74, 12, »
54, 244, 0, 168, 55, 103, 215, 64, 16, 138, 225, 190, 132, 153, 2, »
217, 219, 239, 202, 19, 121, 78 }
Session ID: {}
Cipher Suites: { 0, 5, 0, 4, 0, 9, 0, 10, 0, 18, 0, 19, 0, 3, 0, 17 }
Compression Methods: { 0 }
***
[write] MD5 and SHA1 hashes: len = 59
0000: 01 00 00 37 03 01 3D B6 90 FA C7 94 B4 D7 4A 0C ...7..=.......J.
0010: 36 F4 00 A8 37 67 D7 40 10 8A E1 BE 84 99 02 D9 6...7g.@........
0020: DB EF CA 13 79 4E 00 00 10 00 05 00 04 00 09 00 ....yN..........
0030: 0A 00 12 00 13 00 03 00 11 01 00 ...........
main, WRITE: SSL v3.1 Handshake, length = 59
main, READ: SSL v3.1 Handshake, length = 74
*** ServerHello, v3.1
RandomCookie: GMT: 1018577560 bytes = { 116, 50, 4, 103, 25, 100, 58, »
202, 79, 185, 178, 100, 215, 66, 254, 21, 83, 187, 190, 42, 170, 3, »
132, 110, 82, 148, 160, 92 }
Session ID: {163, 227, 84, 53, 81, 127, 252, 254, 178, 179, 68, 63, »
182, 158, 30, 11, 150, 79, 170, 76, 255, 92, 15, 226, 24, 17, 177, »
219, 158, 177, 187, 143}
Cipher Suite: { 0, 5 }
Compression Method: 0
***
%% Created: [Session-1, SSL_RSA_WITH_RC4_128_SHA]
** SSL_RSA_WITH_RC4_128_SHA
[read] MD5 and SHA1 hashes: len = 74
0000: 02 00 00 46 03 01 3D B6 43 98 74 32 04 67 19 64 ...F..=.C.t2.g.d
0010: 3A CA 4F B9 B2 64 D7 42 FE 15 53 BB BE 2A AA 03 :.O..d.B..S..*..
0020: 84 6E 52 94 A0 5C 20 A3 E3 54 35 51 7F FC FE B2 .nR..\ ..T5Q....
0030: B3 44 3F B6 9E 1E 0B 96 4F AA 4C FF 5C 0F E2 18 .D?.....O.L.\...
0040: 11 B1 DB 9E B1 BB 8F 00 05 00 ..........
main, READ: SSL v3.1 Handshake, length = 1712
...
JSSE provides debugging (to STDOUT) when you set the following
system property: -Djavax.net.debug=all This
will tell you what keystores and truststores are being used, as
well as what is going on during the SSL handshake and
certificate exchange. It will be helpful when trying to
determine what is not working when trying to get an SSL
connection to happen.
Starting with Connector/J 3.1.7, we've made available a variant
of the driver that will automatically send queries to a
read/write master, or a failover or round-robin loadbalanced set
of slaves based on the state of
Connection.getReadOnly() .
An application signals that it wants a transaction to be
read-only by calling
Connection.setReadOnly(true), this
replication-aware connection will use one of the slave
connections, which are load-balanced per-vm using a round-robin
scheme (a given connection is sticky to a slave unless that
slave is removed from service). If you have a write transaction,
or if you have a read that is time-sensitive (remember,
replication in MySQL is asynchronous), set the connection to be
not read-only, by calling
Connection.setReadOnly(false) and the driver
will ensure that further calls are sent to the master MySQL
server. The driver takes care of propagating the current state
of autocommit, isolation level, and catalog between all of the
connections that it uses to accomplish this load balancing
functionality.
To enable this functionality, use the "
com.mysql.jdbc.ReplicationDriver " class when
configuring your application server's connection pool or when
creating an instance of a JDBC driver for your standalone
application. Because it accepts the same URL format as the
standard MySQL JDBC driver, ReplicationDriver
does not currently work with
java.sql.DriverManager -based connection
creation unless it is the only MySQL JDBC driver registered with
the DriverManager .
Here is a short, simple example of how ReplicationDriver might be used in a standalone application.
import java.sql.Connection;
import java.sql.ResultSet;
import java.util.Properties;
import com.mysql.jdbc.ReplicationDriver;
public class ReplicationDriverDemo {
public static void main(String[] args) throws Exception {
ReplicationDriver driver = new ReplicationDriver();
Properties props = new Properties();
// We want this for failover on the slaves
props.put("autoReconnect", "true");
// We want to load balance between the slaves
props.put("roundRobinLoadBalance", "true");
props.put("user", "foo");
props.put("password", "bar");
//
// Looks like a normal MySQL JDBC url, with a
// comma-separated list of hosts, the first
// being the 'master', the rest being any number
// of slaves that the driver will load balance against
//
Connection conn =
driver.connect("jdbc:mysql:replication://master,slave1,slave2,slave3/test",
props);
//
// Perform read/write work on the master
// by setting the read-only flag to "false"
//
conn.setReadOnly(false);
conn.setAutoCommit(false);
conn.createStatement().executeUpdate("UPDATE some_table ....");
conn.commit();
//
// Now, do a query from a slave, the driver automatically picks one
// from the list
//
conn.setReadOnly(true);
ResultSet rs =
conn.createStatement().executeQuery("SELECT a,b FROM alt_table");
.......
}
}You may also want to investigate the Load Balancing JDBC Pool (lbpol) tool, which provides a wrapper around the standard JDBC driver and enables you to use DB connection pools that includes checks for system failures and uneven load distribution. For more information, see Load Balancing JDBC Pool (lbpool).
The table below provides a mapping of the MySQL Error Numbers to
SQL States
Table 4.1. Mapping of MySQL Error Numbers to SQLStates
| MySQL Error Number | MySQL Error Name | Legacy (X/Open) SQLState | SQL Standard SQLState |
|---|---|---|---|
| 1022 | ER_DUP_KEY | S1000 | 23000 |
| 1037 | ER_OUTOFMEMORY | S1001 | HY001 |
| 1038 | ER_OUT_OF_SORTMEMORY | S1001 | HY001 |
| 1040 | ER_CON_COUNT_ERROR | 08004 | 08004 |
| 1042 | ER_BAD_HOST_ERROR | 08004 | 08S01 |
| 1043 | ER_HANDSHAKE_ERROR | 08004 | 08S01 |
| 1044 | ER_DBACCESS_DENIED_ERROR | S1000 | 42000 |
| 1045 | ER_ACCESS_DENIED_ERROR | 28000 | 28000 |
| 1047 | ER_UNKNOWN_COM_ERROR | 08S01 | HY000 |
| 1050 | ER_TABLE_EXISTS_ERROR | S1000 | 42S01 |
| 1051 | ER_BAD_TABLE_ERROR | 42S02 | 42S02 |
| 1052 | ER_NON_UNIQ_ERROR | S1000 | 23000 |
| 1053 | ER_SERVER_SHUTDOWN | S1000 | 08S01 |
| 1054 | ER_BAD_FIELD_ERROR | S0022 | 42S22 |
| 1055 | ER_WRONG_FIELD_WITH_GROUP | S1009 | 42000 |
| 1056 | ER_WRONG_GROUP_FIELD | S1009 | 42000 |
| 1057 | ER_WRONG_SUM_SELECT | S1009 | 42000 |
| 1058 | ER_WRONG_VALUE_COUNT | 21S01 | 21S01 |
| 1059 | ER_TOO_LONG_IDENT | S1009 | 42000 |
| 1060 | ER_DUP_FIELDNAME | S1009 | 42S21 |
| 1061 | ER_DUP_KEYNAME | S1009 | 42000 |
| 1062 | ER_DUP_ENTRY | S1009 | 23000 |
| 1063 | ER_WRONG_FIELD_SPEC | S1009 | 42000 |
| 1064 | ER_PARSE_ERROR | 42000 | 42000 |
| 1065 | ER_EMPTY_QUERY | 42000 | 42000 |
| 1066 | ER_NONUNIQ_TABLE | S1009 | 42000 |
| 1067 | ER_INVALID_DEFAULT | S1009 | 42000 |
| 1068 | ER_MULTIPLE_PRI_KEY | S1009 | 42000 |
| 1069 | ER_TOO_MANY_KEYS | S1009 | 42000 |
| 1070 | ER_TOO_MANY_KEY_PARTS | S1009 | 42000 |
| 1071 | ER_TOO_LONG_KEY | S1009 | 42000 |
| 1072 | ER_KEY_COLUMN_DOES_NOT_EXITS | S1009 | 42000 |
| 1073 | ER_BLOB_USED_AS_KEY | S1009 | 42000 |
| 1074 | ER_TOO_BIG_FIELDLENGTH | S1009 | 42000 |
| 1075 | ER_WRONG_AUTO_KEY | S1009 | 42000 |
| 1080 | ER_FORCING_CLOSE | S1000 | 08S01 |
| 1081 | ER_IPSOCK_ERROR | 08S01 | 08S01 |
| 1082 | ER_NO_SUCH_INDEX | S1009 | 42S12 |
| 1083 | ER_WRONG_FIELD_TERMINATORS | S1009 | 42000 |
| 1084 | ER_BLOBS_AND_NO_TERMINATED | S1009 | 42000 |
| 1090 | ER_CANT_REMOVE_ALL_FIELDS | S1000 | 42000 |
| 1091 | ER_CANT_DROP_FIELD_OR_KEY | S1000 | 42000 |
| 1101 | ER_BLOB_CANT_HAVE_DEFAULT | S1000 | 42000 |
| 1102 | ER_WRONG_DB_NAME | S1000 | 42000 |
| 1103 | ER_WRONG_TABLE_NAME | S1000 | 42000 |
| 1104 | ER_TOO_BIG_SELECT | S1000 | 42000 |
| 1106 | ER_UNKNOWN_PROCEDURE | S1000 | 42000 |
| 1107 | ER_WRONG_PARAMCOUNT_TO_PROCEDURE | S1000 | 42000 |
| 1109 | ER_UNKNOWN_TABLE | S1000 | 42S02 |
| 1110 | ER_FIELD_SPECIFIED_TWICE | S1000 | 42000 |
| 1112 | ER_UNSUPPORTED_EXTENSION | S1000 | 42000 |
| 1113 | ER_TABLE_MUST_HAVE_COLUMNS | S1000 | 42000 |
| 1115 | ER_UNKNOWN_CHARACTER_SET | S1000 | 42000 |
| 1118 | ER_TOO_BIG_ROWSIZE | S1000 | 42000 |
| 1120 | ER_WRONG_OUTER_JOIN | S1000 | 42000 |
| 1121 | ER_NULL_COLUMN_IN_INDEX | S1000 | 42000 |
| 1129 | ER_HOST_IS_BLOCKED | 08004 | HY000 |
| 1130 | ER_HOST_NOT_PRIVILEGED | 08004 | HY000 |
| 1131 | ER_PASSWORD_ANONYMOUS_USER | S1000 | 42000 |
| 1132 | ER_PASSWORD_NOT_ALLOWED | S1000 | 42000 |
| 1133 | ER_PASSWORD_NO_MATCH | S1000 | 42000 |
| 1136 | ER_WRONG_VALUE_COUNT_ON_ROW | S1000 | 21S01 |
| 1138 | ER_INVALID_USE_OF_NULL | S1000 | 42000 |
| 1139 | ER_REGEXP_ERROR | S1000 | 42000 |
| 1140 | ER_MIX_OF_GROUP_FUNC_AND_FIELDS | S1000 | 42000 |
| 1141 | ER_NONEXISTING_GRANT | S1000 | 42000 |
| 1142 | ER_TABLEACCESS_DENIED_ERROR | S1000 | 42000 |
| 1143 | ER_COLUMNACCESS_DENIED_ERROR | S1000 | 42000 |
| 1144 | ER_ILLEGAL_GRANT_FOR_TABLE | S1000 | 42000 |
| 1145 | ER_GRANT_WRONG_HOST_OR_USER | S1000 | 42000 |
| 1146 | ER_NO_SUCH_TABLE | S1000 | 42S02 |
| 1147 | ER_NONEXISTING_TABLE_GRANT | S1000 | 42000 |
| 1148 | ER_NOT_ALLOWED_COMMAND | S1000 | 42000 |
| 1149 | ER_SYNTAX_ERROR | S1000 | 42000 |
| 1152 | ER_ABORTING_CONNECTION | S1000 | 08S01 |
| 1153 | ER_NET_PACKET_TOO_LARGE | S1000 | 08S01 |
| 1154 | ER_NET_READ_ERROR_FROM_PIPE | S1000 | 08S01 |
| 1155 | ER_NET_FCNTL_ERROR | S1000 | 08S01 |
| 1156 | ER_NET_PACKETS_OUT_OF_ORDER | S1000 | 08S01 |
| 1157 | ER_NET_UNCOMPRESS_ERROR | S1000 | 08S01 |
| 1158 | ER_NET_READ_ERROR | S1000 | 08S01 |
| 1159 | ER_NET_READ_INTERRUPTED | S1000 | 08S01 |
| 1160 | ER_NET_ERROR_ON_WRITE | S1000 | 08S01 |
| 1161 | ER_NET_WRITE_INTERRUPTED | S1000 | 08S01 |
| 1162 | ER_TOO_LONG_STRING | S1000 | 42000 |
| 1163 | ER_TABLE_CANT_HANDLE_BLOB | S1000 | 42000 |
| 1164 | ER_TABLE_CANT_HANDLE_AUTO_INCREMENT | S1000 | 42000 |
| 1166 | ER_WRONG_COLUMN_NAME | S1000 | 42000 |
| 1167 | ER_WRONG_KEY_COLUMN | S1000 | 42000 |
| 1169 | ER_DUP_UNIQUE | S1000 | 23000 |
| 1170 | ER_BLOB_KEY_WITHOUT_LENGTH | S1000 | 42000 |
| 1171 | ER_PRIMARY_CANT_HAVE_NULL | S1000 | 42000 |
| 1172 | ER_TOO_MANY_ROWS | S1000 | 42000 |
| 1173 | ER_REQUIRES_PRIMARY_KEY | S1000 | 42000 |
| 1177 | ER_CHECK_NO_SUCH_TABLE | S1000 | 42000 |
| 1178 | ER_CHECK_NOT_IMPLEMENTED | S1000 | 42000 |
| 1179 | ER_CANT_DO_THIS_DURING_AN_TRANSACTION | S1000 | 25000 |
| 1184 | ER_NEW_ABORTING_CONNECTION | S1000 | 08S01 |
| 1189 | ER_MASTER_NET_READ | S1000 | 08S01 |
| 1190 | ER_MASTER_NET_WRITE | S1000 | 08S01 |
| 1203 | ER_TOO_MANY_USER_CONNECTIONS | S1000 | 42000 |
| 1205 | ER_LOCK_WAIT_TIMEOUT | 41000 | 41000 |
| 1207 | ER_READ_ONLY_TRANSACTION | S1000 | 25000 |
| 1211 | ER_NO_PERMISSION_TO_CREATE_USER | S1000 | 42000 |
| 1213 | ER_LOCK_DEADLOCK | 41000 | 40001 |
| 1216 | ER_NO_REFERENCED_ROW | S1000 | 23000 |
| 1217 | ER_ROW_IS_REFERENCED | S1000 | 23000 |
| 1218 | ER_CONNECT_TO_MASTER | S1000 | 08S01 |
| 1222 | ER_WRONG_NUMBER_OF_COLUMNS_IN_SELECT | S1000 | 21000 |
| 1226 | ER_USER_LIMIT_REACHED | S1000 | 42000 |
| 1230 | ER_NO_DEFAULT | S1000 | 42000 |
| 1231 | ER_WRONG_VALUE_FOR_VAR | S1000 | 42000 |
| 1232 | ER_WRONG_TYPE_FOR_VAR | S1000 | 42000 |
| 1234 | ER_CANT_USE_OPTION_HERE | S1000 | 42000 |
| 1235 | ER_NOT_SUPPORTED_YET | S1000 | 42000 |
| 1239 | ER_WRONG_FK_DEF | S1000 | 42000 |
| 1241 | ER_OPERAND_COLUMNS | S1000 | 21000 |
| 1242 | ER_SUBQUERY_NO_1_ROW | S1000 | 21000 |
| 1247 | ER_ILLEGAL_REFERENCE | S1000 | 42S22 |
| 1248 | ER_DERIVED_MUST_HAVE_ALIAS | S1000 | 42000 |
| 1249 | ER_SELECT_REDUCED | S1000 | 01000 |
| 1250 | ER_TABLENAME_NOT_ALLOWED_HERE | S1000 | 42000 |
| 1251 | ER_NOT_SUPPORTED_AUTH_MODE | S1000 | 08004 |
| 1252 | ER_SPATIAL_CANT_HAVE_NULL | S1000 | 42000 |
| 1253 | ER_COLLATION_CHARSET_MISMATCH | S1000 | 42000 |
| 1261 | ER_WARN_TOO_FEW_RECORDS | S1000 | 01000 |
| 1262 | ER_WARN_TOO_MANY_RECORDS | S1000 | 01000 |
| 1263 | ER_WARN_NULL_TO_NOTNULL | S1000 | 01000 |
| 1264 | ER_WARN_DATA_OUT_OF_RANGE | S1000 | 01000 |
| 1265 | ER_WARN_DATA_TRUNCATED | S1000 | 01000 |
| 1280 | ER_WRONG_NAME_FOR_INDEX | S1000 | 42000 |
| 1281 | ER_WRONG_NAME_FOR_CATALOG | S1000 | 42000 |
| 1286 | ER_UNKNOWN_STORAGE_ENGINE | S1000 | 42000 |
Table of Contents
This section provides some general JDBC background.
When you are using JDBC outside of an application server, the
DriverManager class manages the
establishment of Connections.
The DriverManager needs to be told which
JDBC drivers it should try to make Connections with. The
easiest way to do this is to use
Class.forName() on the class that
implements the java.sql.Driver interface.
With MySQL Connector/J, the name of this class is
com.mysql.jdbc.Driver. With this method,
you could use an external configuration file to supply the
driver class name and driver parameters to use when connecting
to a database.
The following section of Java code shows how you might
register MySQL Connector/J from the
main() method of your application. If
testing this code please ensure you read the installation
section first at Chapter 2, Connector/J Installation, to
make sure you have connector installed correctly and the
CLASSPATH set up. Also, ensure that MySQL
is configured to accept external TCP/IP connections.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
// Notice, do not import com.mysql.jdbc.*
// or you will have problems!
public class LoadDriver {
public static void main(String[] args) {
try {
// The newInstance() call is a work around for some
// broken Java implementations
Class.forName("com.mysql.jdbc.Driver").newInstance();
} catch (Exception ex) {
// handle the error
}
}
}
After the driver has been registered with the
DriverManager, you can obtain a
Connection instance that is connected to a
particular database by calling
DriverManager.getConnection():
Example 5.1. Connector/J: Obtaining a connection from the
DriverManager
If you have not already done so, please review the section
Section 5.1.1, “Connecting to MySQL Using the DriverManager Interface”
before working with these examples.
This example shows how you can obtain a
Connection instance from the
DriverManager. There are a few different
signatures for the getConnection()
method. You should see the API documentation that comes with
your JDK for more specific information on how to use them.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
Connection conn = null;
...
try {
conn =
DriverManager.getConnection("jdbc:mysql://localhost/test?" +
"user=monty&password=greatsqldb");
// Do something with the Connection
...
} catch (SQLException ex) {
// handle any errors
System.out.println("SQLException: " + ex.getMessage());
System.out.println("SQLState: " + ex.getSQLState());
System.out.println("VendorError: " + ex.getErrorCode());
}
Once a Connection is established, it
can be used to create Statement and
PreparedStatement objects, as well as
retrieve metadata about the database. This is explained in
the following sections.
Statement objects allow you to execute
basic SQL queries and retrieve the results through the
ResultSet class which is described later.
To create a Statement instance, you
call the createStatement() method on the
Connection object you have retrieved using
one of the DriverManager.getConnection() or
DataSource.getConnection() methods
described earlier.
Once you have a Statement instance, you
can execute a SELECT query by
calling the executeQuery(String) method
with the SQL you want to use.
To update data in the database, use the
executeUpdate(String SQL) method. This
method returns the number of rows matched by the update
statement, not the number of rows that were modified.
If you do not know ahead of time whether the SQL statement
will be a SELECT or an
UPDATE/INSERT,
then you can use the execute(String SQL)
method. This method will return true if the SQL query was a
SELECT, or false if it was an
UPDATE,
INSERT, or
DELETE statement. If the
statement was a SELECT query,
you can retrieve the results by calling the
getResultSet() method. If the statement
was an UPDATE,
INSERT, or
DELETE statement, you can
retrieve the affected rows count by calling
getUpdateCount() on the
Statement instance.
Example 5.2. Connector/J: Using java.sql.Statement to execute a
SELECT query
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSet;
// assume that conn is an already created JDBC connection (see previous examples)
Statement stmt = null;
ResultSet rs = null;
try {
stmt = conn.createStatement();
rs = stmt.executeQuery("SELECT foo FROM bar");
// or alternatively, if you don't know ahead of time that
// the query will be a SELECT...
if (stmt.execute("SELECT foo FROM bar")) {
rs = stmt.getResultSet();
}
// Now do something with the ResultSet ....
}
catch (SQLException ex){
// handle any errors
System.out.println("SQLException: " + ex.getMessage());
System.out.println("SQLState: " + ex.getSQLState());
System.out.println("VendorError: " + ex.getErrorCode());
}
finally {
// it is a good idea to release
// resources in a finally{} block
// in reverse-order of their creation
// if they are no-longer needed
if (rs != null) {
try {
rs.close();
} catch (SQLException sqlEx) { } // ignore
rs = null;
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException sqlEx) { } // ignore
stmt = null;
}
}
Starting with MySQL server version 5.0 when used with
Connector/J 3.1.1 or newer, the
java.sql.CallableStatement interface is
fully implemented with the exception of the
getParameterMetaData() method.
For more information on MySQL stored procedures, please refer to http://dev.mysql.com/doc/mysql/en/stored-routines.html.
Connector/J exposes stored procedure functionality through
JDBC's CallableStatement interface.
Current versions of MySQL server do not return enough
information for the JDBC driver to provide result set
metadata for callable statements. This means that when using
CallableStatement,
ResultSetMetaData may return
NULL.
The following example shows a stored procedure that returns
the value of inOutParam incremented by 1,
and the string passed in using inputParam
as a ResultSet:
Example 5.3. Connector/J: Calling Stored Procedures
CREATE PROCEDURE demoSp(IN inputParam VARCHAR(255), \
INOUT inOutParam INT)
BEGIN
DECLARE z INT;
SET z = inOutParam + 1;
SET inOutParam = z;
SELECT inputParam;
SELECT CONCAT('zyxw', inputParam);
END
To use the demoSp procedure with
Connector/J, follow these steps:
Prepare the callable statement by using
Connection.prepareCall() .
Notice that you have to use JDBC escape syntax, and that the parentheses surrounding the parameter placeholders are not optional:
Example 5.4. Connector/J: Using Connection.prepareCall()
import java.sql.CallableStatement;
...
//
// Prepare a call to the stored procedure 'demoSp'
// with two parameters
//
// Notice the use of JDBC-escape syntax ({call ...})
//
CallableStatement cStmt = conn.prepareCall("{call demoSp(?, ?)}");
cStmt.setString(1, "abcdefg");
Connection.prepareCall() is an
expensive method, due to the metadata retrieval that the
driver performs to support output parameters. For
performance reasons, you should try to minimize
unnecessary calls to
Connection.prepareCall() by reusing
CallableStatement instances in
your code.
Register the output parameters (if any exist)
To retrieve the values of output parameters (parameters
specified as OUT or
INOUT when you created the stored
procedure), JDBC requires that they be specified before
statement execution using the various
registerOutputParameter() methods in
the CallableStatement interface:
Example 5.5. Connector/J: Registering output parameters
import java.sql.Types;
...
//
// Connector/J supports both named and indexed
// output parameters. You can register output
// parameters using either method, as well
// as retrieve output parameters using either
// method, regardless of what method was
// used to register them.
//
// The following examples show how to use
// the various methods of registering
// output parameters (you should of course
// use only one registration per parameter).
//
//
// Registers the second parameter as output, and
// uses the type 'INTEGER' for values returned from
// getObject()
//
cStmt.registerOutParameter(2, Types.INTEGER);
//
// Registers the named parameter 'inOutParam', and
// uses the type 'INTEGER' for values returned from
// getObject()
//
cStmt.registerOutParameter("inOutParam", Types.INTEGER);
...
Set the input parameters (if any exist)
Input and in/out parameters are set as for
PreparedStatement objects. However,
CallableStatement also supports
setting parameters by name:
Example 5.6. Connector/J: Setting CallableStatement input
parameters
...
//
// Set a parameter by index
//
cStmt.setString(1, "abcdefg");
//
// Alternatively, set a parameter using
// the parameter name
//
cStmt.setString("inputParameter", "abcdefg");
//
// Set the 'in/out' parameter using an index
//
cStmt.setInt(2, 1);
//
// Alternatively, set the 'in/out' parameter
// by name
//
cStmt.setInt("inOutParam", 1);
...
Execute the CallableStatement, and
retrieve any result sets or output parameters.
Although CallableStatement supports
calling any of the Statement
execute methods (executeUpdate(),
executeQuery() or
execute()), the most flexible method
to call is execute(), as you do not
need to know ahead of time if the stored procedure returns
result sets:
Example 5.7. Connector/J: Retrieving results and output parameter values
...
boolean hadResults = cStmt.execute();
//
// Process all returned result sets
//
while (hadResults) {
ResultSet rs = cStmt.getResultSet();
// process result set
...
hadResults = cStmt.getMoreResults();
}
//
// Retrieve output parameters
//
// Connector/J supports both index-based and
// name-based retrieval
//
int outputValue = cStmt.getInt(2); // index-based
outputValue = cStmt.getInt("inOutParam"); // name-based
...
Before version 3.0 of the JDBC API, there was no standard way
of retrieving key values from databases that supported auto
increment or identity columns. With older JDBC drivers for
MySQL, you could always use a MySQL-specific method on the
Statement interface, or issue the query
SELECT LAST_INSERT_ID() after issuing an
INSERT to a table that had an
AUTO_INCREMENT key. Using the
MySQL-specific method call isn't portable, and issuing a
SELECT to get the
AUTO_INCREMENT key's value requires another
round-trip to the database, which isn't as efficient as
possible. The following code snippets demonstrate the three
different ways to retrieve AUTO_INCREMENT
values. First, we demonstrate the use of the new JDBC-3.0
method getGeneratedKeys() which is now
the preferred method to use if you need to retrieve
AUTO_INCREMENT keys and have access to
JDBC-3.0. The second example shows how you can retrieve the
same value using a standard SELECT
LAST_INSERT_ID() query. The final example shows how
updatable result sets can retrieve the
AUTO_INCREMENT value when using the
insertRow() method.
Example 5.8. Connector/J: Retrieving AUTO_INCREMENT column values
using Statement.getGeneratedKeys()
Statement stmt = null;
ResultSet rs = null;
try {
//
// Create a Statement instance that we can use for
// 'normal' result sets assuming you have a
// Connection 'conn' to a MySQL database already
// available
stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
java.sql.ResultSet.CONCUR_UPDATABLE);
//
// Issue the DDL queries for the table for this example
//
stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
stmt.executeUpdate(
"CREATE TABLE autoIncTutorial ("
+ "priKey INT NOT NULL AUTO_INCREMENT, "
+ "dataField VARCHAR(64), PRIMARY KEY (priKey))");
//
// Insert one row that will generate an AUTO INCREMENT
// key in the 'priKey' field
//
stmt.executeUpdate(
"INSERT INTO autoIncTutorial (dataField) "
+ "values ('Can I Get the Auto Increment Field?')",
Statement.RETURN_GENERATED_KEYS);
//
// Example of using Statement.getGeneratedKeys()
// to retrieve the value of an auto-increment
// value
//
int autoIncKeyFromApi = -1;
rs = stmt.getGeneratedKeys();
if (rs.next()) {
autoIncKeyFromApi = rs.getInt(1);
} else {
// throw an exception from here
}
rs.close();
rs = null;
System.out.println("Key returned from getGeneratedKeys():"
+ autoIncKeyFromApi);
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException ex) {
// ignore
}
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException ex) {
// ignore
}
}
}
Example 5.9. Connector/J: Retrieving AUTO_INCREMENT column values
using SELECT LAST_INSERT_ID()
Statement stmt = null;
ResultSet rs = null;
try {
//
// Create a Statement instance that we can use for
// 'normal' result sets.
stmt = conn.createStatement();
//
// Issue the DDL queries for the table for this example
//
stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
stmt.executeUpdate(
"CREATE TABLE autoIncTutorial ("
+ "priKey INT NOT NULL AUTO_INCREMENT, "
+ "dataField VARCHAR(64), PRIMARY KEY (priKey))");
//
// Insert one row that will generate an AUTO INCREMENT
// key in the 'priKey' field
//
stmt.executeUpdate(
"INSERT INTO autoIncTutorial (dataField) "
+ "values ('Can I Get the Auto Increment Field?')");
//
// Use the MySQL LAST_INSERT_ID()
// function to do the same thing as getGeneratedKeys()
//
int autoIncKeyFromFunc = -1;
rs = stmt.executeQuery("SELECT LAST_INSERT_ID()");
if (rs.next()) {
autoIncKeyFromFunc = rs.getInt(1);
} else {
// throw an exception from here
}
rs.close();
System.out.println("Key returned from " +
"'SELECT LAST_INSERT_ID()': " +
autoIncKeyFromFunc);
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException ex) {
// ignore
}
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException ex) {
// ignore
}
}
}
Example 5.10. Connector/J: Retrieving AUTO_INCREMENT column values
in Updatable ResultSets
Statement stmt = null;
ResultSet rs = null;
try {
//
// Create a Statement instance that we can use for
// 'normal' result sets as well as an 'updatable'
// one, assuming you have a Connection 'conn' to
// a MySQL database already available
//
stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
java.sql.ResultSet.CONCUR_UPDATABLE);
//
// Issue the DDL queries for the table for this example
//
stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
stmt.executeUpdate(
"CREATE TABLE autoIncTutorial ("
+ "priKey INT NOT NULL AUTO_INCREMENT, "
+ "dataField VARCHAR(64), PRIMARY KEY (priKey))");
//
// Example of retrieving an AUTO INCREMENT key
// from an updatable result set
//
rs = stmt.executeQuery("SELECT priKey, dataField "
+ "FROM autoIncTutorial");
rs.moveToInsertRow();
rs.updateString("dataField", "AUTO INCREMENT here?");
rs.insertRow();
//
// the driver adds rows at the end
//
rs.last();
//
// We should now be on the row we just inserted
//
int autoIncKeyFromRS = rs.getInt("priKey");
rs.close();
rs = null;
System.out.println("Key returned for inserted row: "
+ autoIncKeyFromRS);
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException ex) {
// ignore
}
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException ex) {
// ignore
}
}
}
When you run the preceding example code, you should get the
following output: Key returned from
getGeneratedKeys(): 1 Key returned from
SELECT LAST_INSERT_ID(): 1 Key returned for
inserted row: 2 You should be aware, that at times, it can be
tricky to use the SELECT LAST_INSERT_ID()
query, as that function's value is scoped to a connection. So,
if some other query happens on the same connection, the value
will be overwritten. On the other hand, the
getGeneratedKeys() method is scoped by
the Statement instance, so it can be
used even if other queries happen on the same connection, but
not on the same Statement instance.
This section describes how to use Connector/J in several contexts.
This section provides general background on J2EE concepts that pertain to use of Connector/J.
Connection pooling is a technique of creating and managing a pool of connections that are ready for use by any thread that needs them.
This technique of pooling connections is based on the fact that most applications only need a thread to have access to a JDBC connection when they are actively processing a transaction, which usually take only milliseconds to complete. When not processing a transaction, the connection would otherwise sit idle. Instead, connection pooling enables the idle connection to be used by some other thread to do useful work.
In practice, when a thread needs to do work against a MySQL or other database with JDBC, it requests a connection from the pool. When the thread is finished using the connection, it returns it to the pool, so that it may be used by any other threads that want to use it.
When the connection is loaned out from the pool, it is used
exclusively by the thread that requested it. From a
programming point of view, it is the same as if your thread
called DriverManager.getConnection()
every time it needed a JDBC connection, however with
connection pooling, your thread may end up using either a
new, or already-existing connection.
Connection pooling can greatly increase the performance of your Java application, while reducing overall resource usage. The main benefits to connection pooling are:
Reduced connection creation time
Although this is not usually an issue with the quick connection setup that MySQL offers compared to other databases, creating new JDBC connections still incurs networking and JDBC driver overhead that will be avoided if connections are recycled.
Simplified programming model
When using connection pooling, each individual thread can act as though it has created its own JDBC connection, allowing you to use straight-forward JDBC programming techniques.
Controlled resource usage
If you do not use connection pooling, and instead create a new connection every time a thread needs one, your application's resource usage can be quite wasteful and lead to unpredictable behavior under load.
Remember that each connection to MySQL has overhead (memory, CPU, context switches, and so forth) on both the client and server side. Every connection limits how many resources there are available to your application as well as the MySQL server. Many of these resources will be used whether or not the connection is actually doing any useful work!
Connection pools can be tuned to maximize performance, while keeping resource utilization below the point where your application will start to fail rather than just run slower.
Luckily, Sun has standardized the concept of connection pooling in JDBC through the JDBC-2.0 Optional interfaces, and all major application servers have implementations of these APIs that work fine with MySQL Connector/J.
Generally, you configure a connection pool in your application server configuration files, and access it through the Java Naming and Directory Interface (JNDI). The following code shows how you might use a connection pool from an application deployed in a J2EE application server:
Example 5.11. Connector/J: Using a connection pool with a J2EE application server
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import javax.naming.InitialContext;
import javax.sql.DataSource;
public class MyServletJspOrEjb {
public void doSomething() throws Exception {
/*
* Create a JNDI Initial context to be able to
* lookup the DataSource
*
* In production-level code, this should be cached as
* an instance or static variable, as it can
* be quite expensive to create a JNDI context.
*
* Note: This code only works when you are using servlets
* or EJBs in a J2EE application server. If you are
* using connection pooling in standalone Java code, you
* will have to create/configure datasources using whatever
* mechanisms your particular connection pooling library
* provides.
*/
InitialContext ctx = new InitialContext();
/*
* Lookup the DataSource, which will be backed by a pool
* that the application server provides. DataSource instances
* are also a good candidate for caching as an instance
* variable, as JNDI lookups can be expensive as well.
*/
DataSource ds =
(DataSource)ctx.lookup("java:comp/env/jdbc/MySQLDB");
/*
* The following code is what would actually be in your
* Servlet, JSP or EJB 'service' method...where you need
* to work with a JDBC connection.
*/
Connection conn = null;
Statement stmt = null;
try {
conn = ds.getConnection();
/*
* Now, use normal JDBC programming to work with
* MySQL, making sure to close each resource when you're
* finished with it, which permits the connection pool
* resources to be recovered as quickly as possible
*/
stmt = conn.createStatement();
stmt.execute("SOME SQL QUERY");
stmt.close();
stmt = null;
conn.close();
conn = null;
} finally {
/*
* close any jdbc instances here that weren't
* explicitly closed during normal code path, so
* that we don't 'leak' resources...
*/
if (stmt != null) {
try {
stmt.close();
} catch (sqlexception sqlex) {
// ignore -- as we can't do anything about it here
}
stmt = null;
}
if (conn != null) {
try {
conn.close();
} catch (sqlexception sqlex) {
// ignore -- as we can't do anything about it here
}
conn = null;
}
}
}
}As shown in the example above, after obtaining the JNDI InitialContext, and looking up the DataSource, the rest of the code should look familiar to anyone who has done JDBC programming in the past.
The most important thing to remember when using connection pooling is to make sure that no matter what happens in your code (exceptions, flow-of-control, and so forth), connections, and anything created by them (such as statements or result sets) are closed, so that they may be re-used, otherwise they will be stranded, which in the best case means that the MySQL server resources they represent (such as buffers, locks, or sockets) may be tied up for some time, or worst case, may be tied up forever.
What Is the Best Size for my Connection Pool?
As with all other configuration rules-of-thumb, the answer is: it depends. Although the optimal size depends on anticipated load and average database transaction time, the optimum connection pool size is smaller than you might expect. If you take Sun's Java Petstore blueprint application for example, a connection pool of 15-20 connections can serve a relatively moderate load (600 concurrent users) using MySQL and Tomcat with response times that are acceptable.
To correctly size a connection pool for your application, you should create load test scripts with tools such as Apache JMeter or The Grinder, and load test your application.
An easy way to determine a starting point is to configure your connection pool's maximum number of connections to be unbounded, run a load test, and measure the largest amount of concurrently used connections. You can then work backward from there to determine what values of minimum and maximum pooled connections give the best performance for your particular application.
Validating Connections
MySQL Connector/J has the ability to execute a lightweight ping against a server, in order to validate the connection. In the case of load-balanced connections, this is performed against all active pooled internal connections that are retained. This is beneficial to Java applications using connection pools, as the pool can use this feature to validate connections. Depending on your connection pool and configuration, this validation can be carried out at different times:
Before the pool returns a connection to the application.
When the application returns a connection to the pool.
During periodic checks of idle connections.
In order to use this feature you need to specify a
validation query in your connection pool that starts with
/* ping */. Note the syntax must be
exactly as specified. This will cause the driver send a ping
to the server and return a fake, light-weight, result set.
When using a ReplicationConnection or
LoadBalancedConnection, the ping will be
sent across all active connections.
It is critical that the syntax be specified correctly. For example, consider the following snippets:
sql = "/* PING */ SELECT 1"; sql = "SELECT 1 /* ping*/"; sql = "/*ping*/ SELECT 1"; sql = " /* ping */ SELECT 1"; sql = "/*to ping or not to ping*/ SELECT 1";
None of the above statements will work. This is because the ping syntax is sensitive to whitespace, capitalization, and placement. The syntax needs to be exact for reasons of efficiency, as this test is done for every statement that is executed:
protected static final String PING_MARKER = "/* ping */";
...
if (sql.charAt(0) == '/') {
if (sql.startsWith(PING_MARKER)) {
doPingInstead();
...
All of the previous statements will issue a normal
SELECT statement and will
not be transformed into the
lightweight ping. Further, for load-balanced connections the
statement will be executed against one connection in the
internal pool, rather than validating each underlying
physical connection. This results in the non-active physical
connections assuming a stale state, and they may die. If
Connector/J then re-balances it may select a dead
connection, resulting in an exception being passed to the
application. To help prevent this you can use
loadBalanceValidateConnectionOnSwapServer
to validate the connection before use.
If your Connector/J deployment uses a connection pool that
allows you to specify a validation query, this should be
taken advantage of, but ensure that the query starts
exactly with /* ping
*/. This is particularly important if you are
using the load-balancing or replication-aware features of
Connector/J, as it will help keep alive connections which
otherwise will go stale and die, causing problems later.
Connector/J has long provided an effective means to distribute read/write load across multiple MySQL server instances for Cluster or master-master replication deployments, but until version 5.1.13, managing such deployments frequently required a service outage to redeploy a new configuration. Given that the ease of scaling out by adding additional MySQL Cluster (server) instances is a key element in that product offering, which is also naturally targeted at deployments with very strict availability requirements, it was necessary to add support for online changes of this nature. This is also critical for online upgrades, as the alternative is to take a MySQL Cluster server instance down hard, which will lose any in-process transactions and will also generate application exceptions, if any application is trying to use that particular server instance. Connector/J now has the ability to dynamically configure load-balanced connections.
There are two connection string options associated with this functionality:
loadBalanceConnectionGroup – This
provides the ability to group connections from different
sources. This allows you to manage these JDBC sources
within a single class-loader in any combination you
choose. If they use the same configuration, and you want
to manage them as a logical single group, give them the
same name. This is the key property for management, if
you do not define a name (string) for
loadBalanceConnectionGroup, you
cannot manage the connections. All load-balanced
connections sharing the same
loadBalanceConnectionGroup value,
regardless of how the application creates them, will be
managed together.
loadBalanceEnableJMX – The ability
to manage the connections is exposed when you define a
loadBalanceConnectionGroup, but if
you want to manage this externally, it is necessary to
enable JMX by setting this property to
true. This enables a JMX
implementation, which exposes the management and
monitoring operations of a connection group. Further,
you need to start your application with the
-Dcom.sun.management.jmxremote JVM
flag. You can then perform connect and perform
operations using a JMX client such as
jconsole.
Once a connection has been made using the correct connection string options, a number of monitoring properties are available:
Current active host count
Current active physical connection count
Current active logical connection count
Total logical connections created
Total transaction count
The following management operations can also be performed:
Add host
Remove host
The JMX interface,
com.mysql.jdbc.jmx.LoadBalanceConnectionGroupManagerMBean,
has the following methods:
int getActiveHostCount(String group);
int getTotalHostCount(String group);
long getTotalLogicalConnectionCount(String group);
long getActiveLogicalConnectionCount(String group);
long getActivePhysicalConnectionCount(String group);
long getTotalPhysicalConnectionCount(String group);
long getTotalTransactionCount(String group);
void removeHost(String group, String host) throws SQLException;
void stopNewConnectionsToHost(String group, String host) throws SQLException;
void addHost(String group, String host, boolean forExisting);
String getActiveHostsList(String group);
String getRegisteredConnectionGroups();
The getRegisteredConnectionGroups()
method will return the names of all connection groups
defined in that class-loader.
You can test this setup with the following code:
public class Test {
private static String URL = "jdbc:mysql:loadbalance://" +
"localhost:3306,localhost:3310/test?" +
"loadBalanceConnectionGroup=first&loadBalanceEnableJMX=true";
public static void main(String[] args) throws Exception {
new Thread(new Repeater()).start();
new Thread(new Repeater()).start();
new Thread(new Repeater()).start();
}
static Connection getNewConnection() throws SQLException, ClassNotFoundException {
Class.forName("com.mysql.jdbc.Driver");
return DriverManager.getConnection(URL, "root", "");
}
static void executeSimpleTransaction(Connection c, int conn, int trans){
try {
c.setAutoCommit(false);
Statement s = c.createStatement();
s.executeQuery("SELECT SLEEP(1) /* Connection: " + conn + ", transaction: " + trans + " */");
c.commit();
} catch (SQLException e) {
e.printStackTrace();
}
}
public static class Repeater implements Runnable {
public void run() {
for(int i=0; i < 100; i++){
try {
Connection c = getNewConnection();
for(int j=0; j < 10; j++){
executeSimpleTransaction(c, i, j);
Thread.sleep(Math.round(100 * Math.random()));
}
c.close();
Thread.sleep(100);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
}
After compiling, the application can be started with the
-Dcom.sun.management.jmxremote flag, to
enable remote management. jconsole can
then be started. The Test main class will be listed by
jconsole. Select this and click
. You can then navigate to the
com.mysql.jdbc.jmx.LoadBalanceConnectionGroupManager
bean. At this point you can click on various operations and
examine the returned result.
If you now had an additional instance of MySQL running on
port 3309, you could ensure that Connector/J starts using it
by using the addHost(), which is exposed
in jconsole. Note that these operations
can be performed dynamically without having to stop the
application running.
Connector/J provides a useful load-balancing implementation
for Cluster or multi-master deployments. As of Connector/J
5.1.12, this same implementation is used for balancing load
between read-only slaves with
ReplicationDriver. When trying to balance
workload between multiple servers, the driver has to
determine when it is safe to swap servers, doing so in the
middle of a transaction, for example, could cause problems.
It is important not to lose state information. For this
reason, Connector/J will only try to pick a new server when
one of the following happens:
At transaction boundaries (transactions are explicitly committed or rolled back).
A communication exception (SQL State starting with "08") is encountered.
When a SQLException matches
conditions defined by user, using the extension points
defined by the
loadBalanceSQLStateFailover,
loadBalanceSQLExceptionSubclassFailover
or loadBalanceExceptionChecker
properties.
The third condition revolves around three new properties
introduced with Connector/J 5.1.13. It allows you to control
which SQLExceptions trigger failover.
loadBalanceExceptionChecker - The
loadBalanceExceptionChecker property
is really the key. This takes a fully-qualified class
name which implements the new
com.mysql.jdbc.LoadBalanceExceptionChecker
interface. This interface is very simple, and you only
need to implement the following method:
public boolean shouldExceptionTriggerFailover(SQLException ex)
A SQLException is passed in, and a
boolean returned. True triggers a
failover, false does not.
You can use this to implement your own custom logic. An example where this might be useful is when dealing with transient errors when using MySQL Cluster, where certain buffers may become overloaded. The following code snippet illustrates this:
public class NdbLoadBalanceExceptionChecker
extends StandardLoadBalanceExceptionChecker {
public boolean shouldExceptionTriggerFailover(SQLException ex) {
return super.shouldExceptionTriggerFailover(ex)
|| checkNdbException(ex);
}
private boolean checkNdbException(SQLException ex){
// Have to parse the message since most NDB errors
// are mapped to the same DEMC.
return (ex.getMessage().startsWith("Lock wait timeout exceeded") ||
(ex.getMessage().startsWith("Got temporary error")
&& ex.getMessage().endsWith("from NDB")));
}
}
The code above extends
com.mysql.jdbc.StandardLoadBalanceExceptionChecker,
which is the default implementation. There are a few
convenient shortcuts built into this, for those who want
to have some level of control using properties, without
writing Java code. This default implementation uses the
two remaining properties:
loadBalanceSQLStateFailover and
loadBalanceSQLExceptionSubclassFailover.
loadBalanceSQLStateFailover - allows
you to define a comma-delimited list of
SQLState code prefixes, against which
a SQLException is compared. If the
prefix matches, failover is triggered. So, for example,
the following would trigger a failover if a given
SQLException starts with "00", or is
"12345":
loadBalanceSQLStateFailover=00,12345
loadBalanceSQLExceptionSubclassFailover
- can be used in conjunction with
loadBalanceSQLStateFailover or on its
own. If you want certain subclasses of
SQLException to trigger failover,
simply provide a comma-delimited list of fully-qualified
class or interface names to check against. For example,
if you want all
SQLTransientConnectionExceptions to
trigger failover, you would specify:
loadBalanceSQLExceptionSubclassFailover=java.sql.SQLTransientConnectionException
While the three fail-over conditions enumerated earlier suit
most situations, if auto-commit is
enabled, Connector/J never re-balances, and continues using
the same physical connection. This can be problematic,
particularly when load-balancing is being used to distribute
read-only load across multiple slaves. However, Connector/J
can be configured to re-balance after a certain number of
statements are executed, when auto-commit
is enabled. This functionality is dependent upon the
following properties:
loadBalanceAutoCommitStatementThreshold
– defines the number of matching statements which will
trigger the driver to potentially swap physical server
connections. The default value, 0, retains the behavior
that connections with auto-commit
enabled are never balanced.
loadBalanceAutoCommitStatementRegex
– the regular expression against which statements must
match. The default value, blank, matches all statements.
So, for example, using the following properties will
cause Connector/J to re-balance after every third
statement that contains the string “test”:
loadBalanceAutoCommitStatementThreshold=3 loadBalanceAutoCommitStatementRegex=.*test.*
loadBalanceAutoCommitStatementRegex
can prove useful in a number of situations. Your
application may use temporary tables, server-side
session state variables, or connection state, where
letting the driver arbitrarily swap physical connections
before processing is complete could cause data loss or
other problems. This allows you to identify a trigger
statement that is only executed when it is safe to swap
physical connections.
The following instructions are based on the instructions for Tomcat-5.x, available at http://tomcat.apache.org/tomcat-5.5-doc/jndi-datasource-examples-howto.html which is current at the time this document was written.
First, install the .jar file that comes with Connector/J in
$CATALINA_HOME/common/lib so that it is
available to all applications installed in the container.
Next, Configure the JNDI DataSource by adding a declaration
resource to
$CATALINA_HOME/conf/server.xml in the
context that defines your web application:
<Context ....>
...
<Resource name="jdbc/MySQLDB"
auth="Container"
type="javax.sql.DataSource"/>
<!-- The name you used above, must match _exactly_ here!
The connection pool will be bound into JNDI with the name
"java:/comp/env/jdbc/MySQLDB"
-->
<ResourceParams name="jdbc/MySQLDB">
<parameter>
<name>factory</name>
<value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
</parameter>
<!-- Don't set this any higher than max_connections on your
MySQL server, usually this should be a 10 or a few 10's
of connections, not hundreds or thousands -->
<parameter>
<name>maxActive</name>
<value>10</value>
</parameter>
<!-- You don't want to many idle connections hanging around
if you can avoid it, only enough to soak up a spike in
the load -->
<parameter>
<name>maxIdle</name>
<value>5</value>
</parameter>
<!-- Don't use autoReconnect=true, it's going away eventually
and it's a crutch for older connection pools that couldn't
test connections. You need to decide whether your application
is supposed to deal with SQLExceptions (hint, it should), and
how much of a performance penalty you're willing to pay
to ensure 'freshness' of the connection -->
<parameter>
<name>validationQuery</name>
<value>SELECT 1</value> <-- See discussion below for update to this option -->
</parameter>
<!-- The most conservative approach is to test connections
before they're given to your application. For most applications
this is okay, the query used above is very small and takes
no real server resources to process, other than the time used
to traverse the network.
If you have a high-load application you'll need to rely on
something else. -->
<parameter>
<name>testOnBorrow</name>
<value>true</value>
</parameter>
<!-- Otherwise, or in addition to testOnBorrow, you can test
while connections are sitting idle -->
<parameter>
<name>testWhileIdle</name>
<value>true</value>
</parameter>
<!-- You have to set this value, otherwise even though
you've asked connections to be tested while idle,
the idle evicter thread will never run -->
<parameter>
<name>timeBetweenEvictionRunsMillis</name>
<value>10000</value>
</parameter>
<!-- Don't allow connections to hang out idle too long,
never longer than what wait_timeout is set to on the
server...A few minutes or even fraction of a minute
is sometimes okay here, it depends on your application
and how much spikey load it will see -->
<parameter>
<name>minEvictableIdleTimeMillis</name>
<value>60000</value>
</parameter>
<!-- Username and password used when connecting to MySQL -->
<parameter>
<name>username</name>
<value>someuser</value>
</parameter>
<parameter>
<name>password</name>
<value>somepass</value>
</parameter>
<!-- Class name for the Connector/J driver -->
<parameter>
<name>driverClassName</name>
<value>com.mysql.jdbc.Driver</value>
</parameter>
<!-- The JDBC connection url for connecting to MySQL, notice
that if you want to pass any other MySQL-specific parameters
you should pass them here in the URL, setting them using the
parameter tags above will have no effect, you will also
need to use & to separate parameter values as the
ampersand is a reserved character in XML -->
<parameter>
<name>url</name>
<value>jdbc:mysql://localhost:3306/test</value>
</parameter>
</ResourceParams>
</Context>
Note that Connector/J 5.1.3 introduced a facility whereby,
rather than use a validationQuery value of
SELECT 1, it is possible to use
validationQuery with a value set to
/* ping */. This sends a ping to the server
which then returns a fake result set. This is a lighter weight
solution. It also has the advantage that if using
ReplicationConnection or
LoadBalancedConnection type connections,
the ping will be sent across all active connections. The
following XML snippet illustrates how to select this option:
<parameter> <name>validationQuery</name> <value>/* ping */</value> </parameter>
Note that /* ping */ has to be specified
exactly.
In general, you should follow the installation instructions that come with your version of Tomcat, as the way you configure datasources in Tomcat changes from time-to-time, and unfortunately if you use the wrong syntax in your XML file, you will most likely end up with an exception similar to the following:
Error: java.sql.SQLException: Cannot load JDBC driver class 'null ' SQL state: null
These instructions cover JBoss-4.x. To make the JDBC driver
classes available to the application server, copy the .jar
file that comes with Connector/J to the
lib directory for your server
configuration (which is usually called
default). Then, in the same configuration
directory, in the subdirectory named deploy, create a
datasource configuration file that ends with "-ds.xml", which
tells JBoss to deploy this file as a JDBC Datasource. The file
should have the following contents:
<datasources>
<local-tx-datasource>
<!-- This connection pool will be bound into JNDI with the name
"java:/MySQLDB" -->
<jndi-name>MySQLDB</jndi-name>
<connection-url>jdbc:mysql://localhost:3306/dbname</connection-url>
<driver-class>com.mysql.jdbc.Driver</driver-class>
<user-name>user</user-name>
<password>pass</password>
<min-pool-size>5</min-pool-size>
<!-- Don't set this any higher than max_connections on your
MySQL server, usually this should be a 10 or a few 10's
of connections, not hundreds or thousands -->
<max-pool-size>20</max-pool-size>
<!-- Don't allow connections to hang out idle too long,
never longer than what wait_timeout is set to on the
server...A few minutes is usually okay here,
it depends on your application
and how much spikey load it will see -->
<idle-timeout-minutes>5</idle-timeout-minutes>
<!-- If you're using Connector/J 3.1.8 or newer, you can use
our implementation of these to increase the robustness
of the connection pool. -->
<exception-sorter-class-name>
com.mysql.jdbc.integration.jboss.ExtendedMysqlExceptionSorter
</exception-sorter-class-name>
<valid-connection-checker-class-name>
com.mysql.jdbc.integration.jboss.MysqlValidConnectionChecker
</valid-connection-checker-class-name>
</local-tx-datasource>
</datasources> The Spring Framework is a Java-based application framework designed for assisting in application design by providing a way to configure components. The technique used by Spring is a well known design pattern called Dependency Injection (see Inversion of Control Containers and the Dependency Injection pattern). This article will focus on Java-oriented access to MySQL databases with Spring 2.0. For those wondering, there is a .NET port of Spring appropriately named Spring.NET.
Spring is not only a system for configuring components, but also includes support for aspect oriented programming (AOP). This is one of the main benefits and the foundation for Spring's resource and transaction management. Spring also provides utilities for integrating resource management with JDBC and Hibernate.
For the examples in this section the MySQL world sample database will be used. The first task is to set up a MySQL data source through Spring. Components within Spring use the "bean" terminology. For example, to configure a connection to a MySQL server supporting the world sample database you might use:
<util:map id="dbProps">
<entry key="db.driver" value="com.mysql.jdbc.Driver"/>
<entry key="db.jdbcurl" value="jdbc:mysql://localhost/world"/>
<entry key="db.username" value="myuser"/>
<entry key="db.password" value="mypass"/>
</util:map>
In the above example we are assigning values to properties that will be used in the configuration. For the datasource configuration:
<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${db.driver}"/>
<property name="url" value="${db.jdbcurl}"/>
<property name="username" value="${db.username}"/>
<property name="password" value="${db.password}"/>
</bean>
The placeholders are used to provide values for properties of this bean. This means that you can specify all the properties of the configuration in one place instead of entering the values for each property on each bean. We do, however, need one more bean to pull this all together. The last bean is responsible for actually replacing the placeholders with the property values.
<bean
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="properties" ref="dbProps"/>
</bean>
Now that we have our MySQL data source configured and ready to go, we write some Java code to access it. The example below will retrieve three random cities and their corresponding country using the data source we configured with Spring.
// Create a new application context. this processes the Spring config
ApplicationContext ctx =
new ClassPathXmlApplicationContext("ex1appContext.xml");
// Retrieve the data source from the application context
DataSource ds = (DataSource) ctx.getBean("dataSource");
// Open a database connection using Spring's DataSourceUtils
Connection c = DataSourceUtils.getConnection(ds);
try {
// retrieve a list of three random cities
PreparedStatement ps = c.prepareStatement(
"select City.Name as 'City', Country.Name as 'Country' " +
"from City inner join Country on City.CountryCode = Country.Code " +
"order by rand() limit 3");
ResultSet rs = ps.executeQuery();
while(rs.next()) {
String city = rs.getString("City");
String country = rs.getString("Country");
System.out.printf("The city %s is in %s%n", city, country);
}
} catch (SQLException ex) {
// something has failed and we print a stack trace to analyse the error
ex.printStackTrace();
// ignore failure closing connection
try { c.close(); } catch (SQLException e) { }
} finally {
// properly release our connection
DataSourceUtils.releaseConnection(c, ds);
}This is very similar to normal JDBC access to MySQL with the main difference being that we are using DataSourceUtils instead of the DriverManager to create the connection.
While it may seem like a small difference, the implications are somewhat far reaching. Spring manages this resource in a way similar to a container managed data source in a J2EE application server. When a connection is opened, it can be subsequently accessed in other parts of the code if it is synchronized with a transaction. This makes it possible to treat different parts of your application as transactional instead of passing around a database connection.
Spring makes extensive use of the Template method design
pattern (see
Template
Method Pattern). Our immediate focus will be on the
JdbcTemplate and related classes,
specifically NamedParameterJdbcTemplate.
The template classes handle obtaining and releasing a
connection for data access when one is needed.
The next example shows how to use
NamedParameterJdbcTemplate inside of a
DAO (Data Access Object) class to retrieve a random city
given a country code.
public class Ex2JdbcDao {
/**
* Data source reference which will be provided by Spring.
*/
private DataSource dataSource;
/**
* Our query to find a random city given a country code. Notice
* the ":country" parameter toward the end. This is called a
* named parameter.
*/
private String queryString = "select Name from City " +
"where CountryCode = :country order by rand() limit 1";
/**
* Retrieve a random city using Spring JDBC access classes.
*/
public String getRandomCityByCountryCode(String cntryCode) {
// A template that permits using queries with named parameters
NamedParameterJdbcTemplate template =
new NamedParameterJdbcTemplate(dataSource);
// A java.util.Map is used to provide values for the parameters
Map params = new HashMap();
params.put("country", cntryCode);
// We query for an Object and specify what class we are expecting
return (String)template.queryForObject(queryString, params, String.class);
}
/**
* A JavaBean setter-style method to allow Spring to inject the data source.
* @param dataSource
*/
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
}
The focus in the above code is on the
getRandomCityByCountryCode() method. We
pass a country code and use the
NamedParameterJdbcTemplate to query for a
city. The country code is placed in a Map with the key
"country", which is the parameter is named in the SQL query.
To access this code, you need to configure it with Spring by providing a reference to the data source.
<bean id="dao" class="code.Ex2JdbcDao">
<property name="dataSource" ref="dataSource"/>
</bean>
At this point, we can just grab a reference to the DAO from
Spring and call
getRandomCityByCountryCode().
// Create the application context
ApplicationContext ctx =
new ClassPathXmlApplicationContext("ex2appContext.xml");
// Obtain a reference to our DAO
Ex2JdbcDao dao = (Ex2JdbcDao) ctx.getBean("dao");
String countryCode = "USA";
// Find a few random cities in the US
for(int i = 0; i < 4; ++i)
System.out.printf("A random city in %s is %s%n", countryCode,
dao.getRandomCityByCountryCode(countryCode));
This example shows how to use Spring's JDBC classes to
completely abstract away the use of traditional JDBC classes
including Connection and
PreparedStatement.
You might be wondering how we can add transactions into our code if we do not deal directly with the JDBC classes. Spring provides a transaction management package that not only replaces JDBC transaction management, but also enables declarative transaction management (configuration instead of code).
To use transactional database access, we will need to change the storage engine of the tables in the world database. The downloaded script explicitly creates MyISAM tables which do not support transactional semantics. The InnoDB storage engine does support transactions and this is what we will be using. We can change the storage engine with the following statements.
ALTER TABLE City ENGINE=InnoDB; ALTER TABLE Country ENGINE=InnoDB; ALTER TABLE CountryLanguage ENGINE=InnoDB;
A good programming practice emphasized by Spring is separating interfaces and implementations. What this means is that we can create a Java interface and only use the operations on this interface without any internal knowledge of what the actual implementation is. We will let Spring manage the implementation and with this it will manage the transactions for our implementation.
First you create a simple interface:
public interface Ex3Dao {
Integer createCity(String name, String countryCode,
String district, Integer population);
}This interface contains one method that will create a new city record in the database and return the id of the new record. Next you need to create an implementation of this interface.
public class Ex3DaoImpl implements Ex3Dao {
protected DataSource dataSource;
protected SqlUpdate updateQuery;
protected SqlFunction idQuery;
public Integer createCity(String name, String countryCode,
String district, Integer population) {
updateQuery.update(new Object[] { name, countryCode,
district, population });
return getLastId();
}
protected Integer getLastId() {
return idQuery.run();
}
}You can see that we only operate on abstract query objects here and do not deal directly with the JDBC API. Also, this is the complete implementation. All of our transaction management will be dealt with in the configuration. To get the configuration started, we need to create the DAO.
<bean id="dao" class="code.Ex3DaoImpl">
<property name="dataSource" ref="dataSource"/>
<property name="updateQuery">...</property>
<property name="idQuery">...</property>
</bean>
Now you need to set up the transaction configuration. The
first thing you must do is create transaction manager to
manage the data source and a specification of what
transaction properties are required for the
dao methods.
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"/>
</bean>
<tx:advice id="txAdvice" transaction-manager="transactionManager">
<tx:attributes>
<tx:method name="*"/>
</tx:attributes>
</tx:advice>
The preceding code creates a transaction manager that
handles transactions for the data source provided to it. The
txAdvice uses this transaction manager
and the attributes specify to create a transaction for all
methods. Finally you need to apply this advice with an AOP
pointcut.
<aop:config>
<aop:pointcut id="daoMethods"
expression="execution(* code.Ex3Dao.*(..))"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="daoMethods"/>
</aop:config>
This basically says that all methods called on the
Ex3Dao interface will be wrapped in a
transaction. To make use of this, you only have to retrieve
the dao from the application context and
call a method on the dao instance.
Ex3Dao dao = (Ex3Dao) ctx.getBean("dao");
Integer id = dao.createCity(name, countryCode, district, pop);We can verify from this that there is no transaction management happening in our Java code and it is all configured with Spring. This is a very powerful notion and regarded as one of the most beneficial features of Spring.
In many situations, such as web applications, there will be
a large number of small database transactions. When this is
the case, it usually makes sense to create a pool of
database connections available for web requests as needed.
Although MySQL does not spawn an extra process when a
connection is made, there is still a small amount of
overhead to create and set up the connection. Pooling of
connections also alleviates problems such as collecting
large amounts of sockets in the TIME_WAIT
state.
Setting up pooling of MySQL connections with Spring is as
simple as changing the data source configuration in the
application context. There are a number of configurations
that we can use. The first example is based on the
Jakarta
Commons DBCP library. The example below replaces the
source configuration that was based on
DriverManagerDataSource with DBCP's
BasicDataSource.
<bean id="dataSource" destroy-method="close"
class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="${db.driver}"/>
<property name="url" value="${db.jdbcurl}"/>
<property name="username" value="${db.username}"/>
<property name="password" value="${db.password}"/>
<property name="initialSize" value="3"/>
</bean>
The configuration of the two solutions is very similar. The
difference is that DBCP will pool connections to the
database instead of creating a new connection every time one
is requested. We have also set a parameter here called
initialSize. This tells DBCP that we want
three connections in the pool when it is created.
Another way to configure connection pooling is to configure
a data source in our J2EE application server. Using JBoss as
an example, you can set up the MySQL connection pool by
creating a file called
mysql-local-ds.xml and placing it in
the server/default/deploy directory in JBoss. Once we have
this setup, we can use JNDI to look it up. With Spring, this
lookup is very simple. The data source configuration looks
like this.
<jee:jndi-lookup id="dataSource" jndi-name="java:MySQL_DS"/>
This section explains how to use MySQL Connector/J with Glassfish ™ Server Open Source Edition 3.0.1. Glassfish can be downloaded from the Glassfish website.
Once Glassfish is installed you will need to make sure it can
access MySQL Connector/J. To do this copy the MySQL Connector/J JAR file to the
directory
GLASSFISH_INSTALL/glassfish/libmysql-connector-java-5.1.12-bin.jar to
C:\glassfishv3\glassfish\lib. Restart the
Glassfish Application Server.
You are now ready to create JDBC Connection Pools and JDBC Resources.
Creating a Connection Pool
In the Glassfish Administration Console, using the navigation tree navigate to Resources, JDBC, Connection Pools.
In the JDBC Connection Pools frame click . You will enter a two step wizard.
In the Name field under
General Settings enter the name for
the connection pool, for example enter
MySQLConnPool.
In the Resource Type field, select
javax.sql.DataSource from the drop-down
listbox.
In the Database Vendor field, select
MySQL from the drop-down listbox. Click
to go to the next page of the
wizard.
You can accept the default settings for General Settings, Pool Settings and Transactions for this example. Scroll down to Additional Properties.
In Additional Properties you will need to ensure the following properties are set:
ServerName - The
server you wish to connect to. For local testing this
will be localhost.
User - The user name with which to connect to MySQL.
Password - The corresponding password for the user.
DatabaseName - The
database you wish to connect to, for example the
sample MySQL database World.
Click to exit the wizard. You will be taken to the JDBC Connection Pools page where all current connection pools, including the one you just created, will be displayed.
In the JDBC Connection Pools frame click on the connection pool you just created. Here you can review and edit information about the connection pool.
To test your connection pool click the button at the top of the frame. A message will be displayed confirming correct operation or otherwise. If an error message is received recheck the previous steps, and ensure that MySQL Connector/J has been correctly copied into the previously specified location.
Now that you have created a connection pool you will also need to create a JDBC Resource (data source) for use by your application.
Creating a JDBC Resource
Your Java application will usually reference a data source object to establish a connection with the database. This needs to be created first using the following procedure.
Using the navigation tree in the Glassfish Administration Console, navigate to Resources, JDBC, JDBC Resources. A list of resources will be displayed in the JDBC Resources frame.
Click . The New JDBC Resource frame will be displayed.
In the JNDI Name field, enter the
JNDI name that will be used to access this resource, for
example enter jdbc/MySQLDataSource.
In the Pool Name field, select a connection pool you want this resource to use from the drop-down listbox.
Optionally, you can enter a description into the Description field.
Additional properties can be added if required.
Click to create the new JDBC resource. The JDBC Resources frame will list all available JDBC Resources.
This section shows how to deploy a simple JSP application on Glassfish, that connects to a MySQL database.
This example assumes you have already set up a suitable
Connection Pool and JDBC Resource, as explained in the
preceding sections. It is also assumed you have a sample
database installed, such as world.
The main application code, index.jsp is
presented here:
<%@ page import="java.sql.*, javax.sql.*, java.io.*, javax.naming.*" %>
<html>
<head><title>Hello world from JSP</title></head>
<body>
<%
InitialContext ctx;
DataSource ds;
Connection conn;
Statement stmt;
ResultSet rs;
try {
ctx = new InitialContext();
ds = (DataSource) ctx.lookup("java:comp/env/jdbc/MySQLDataSource");
//ds = (DataSource) ctx.lookup("jdbc/MySQLDataSource");
conn = ds.getConnection();
stmt = conn.createStatement();
rs = stmt.executeQuery("SELECT * FROM Country");
while(rs.next()) {
%>
<h3>Name: <%= rs.getString("Name") %></h3>
<h3>Population: <%= rs.getString("Population") %></h3>
<%
}
}
catch (SQLException se) {
%>
<%= se.getMessage() %>
<%
}
catch (NamingException ne) {
%>
<%= ne.getMessage() %>
<%
}
%>
</body>
</html>
In addition two XML files are required:
web.xml, and
sun-web.xml. There may be other files
present, such as classes and images. These files are
organized into the directory structure as follows:
index.jsp WEB-INF | - web.xml - sun-web.xml
The code for web.xml is:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>HelloWebApp</display-name>
<distributable/>
<resource-ref>
<res-ref-name>jdbc/MySQLDataSource</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
<res-sharing-scope>Shareable</res-sharing-scope>
</resource-ref>
</web-app>
The code for sun-web.xml is:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sun-web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Application Server 8.1 Servlet 2.4//EN" "http://www.sun.com/software/appserver/dtds/sun-web-app_2_4-1.dtd">
<sun-web-app>
<context-root>HelloWebApp</context-root>
<resource-ref>
<res-ref-name>jdbc/MySQLDataSource</res-ref-name>
<jndi-name>jdbc/MySQLDataSource</jndi-name>
</resource-ref>
</sun-web-app>
These XML files illustrate a very important aspect of
running JDBC applications on Glassfish. On Glassfish it is
important to map the string specified for a JDBC resource to
its JNDI name, as set up in the Glassfish administration
console. In this example, the JNDI name for the JDBC
resource, as specified in the Glassfish Administration
console when creating the JDBC Resource, was
jdbc/MySQLDataSource. This must be mapped
to the name given in the application. In this example the
name specified in the application,
jdbc/MySQLDataSource, and the JNDI name,
happen to be the same, but this does not necessarily have to
be the case. Note that the XML element <res-ref-name>
is used to specify the name as used in the application
source code, and this is mapped to the JNDI name specified
using the <jndi-name> element, in the file
sun-web.xml. The resource also has to
be created in the web.xml file,
although the mapping of the resource to a JNDI name takes
place in the sun-web.xml file.
If you do not have this mapping set up correctly in the XML files you will not be able to lookup the data source using a JNDI lookup string such as:
ds = (DataSource) ctx.lookup("java:comp/env/jdbc/MySQLDataSource");You will still be able to access the data source directly using:
ds = (DataSource) ctx.lookup("jdbc/MySQLDataSource");With the source files in place, in the correct directory structure, you are ready to deploy the application:
In the navigation tree, navigate to Applications - the Applications frame will be displayed. Click .
You can now deploy an application packaged into a single WAR file from a remote client, or you can choose a packaged file or directory that is locally accessible to the server. If you are simply testing an application locally you can simply point Glassfish at the directory that contains your application, without needing to package the application into a WAR file.
Now select the application type from the
Type drop-down listbox, which in
this example is Web application.
Click OK.
Now, when you navigate to the
Applications frame, you will have the
option to Launch,
Redeploy, or
Restart your application. You can test
your application by clicking Launch.
The application will connection to the MySQL database and
display the Name and Population of countries in the
Country table.
This section describes a simple servlet that can be used in
the Glassfish environment to access a MySQL database. As
with the previous section, this example assumes the sample
database world is installed.
The project is set up with the following directory structure:
index.html
WEB-INF
|
- web.xml
- sun-web.xml
- classes
|
- HelloWebServlet.java
- HelloWebServlet.class
The code for the servlet, located in
HelloWebServlet.java, is as follows:
import javax.servlet.http.*;
import javax.servlet.*;
import java.io.*;
import java.sql.*;
import javax.sql.*;
import javax.naming.*;
public class HelloWebServlet extends HttpServlet {
InitialContext ctx = null;
DataSource ds = null;
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
String sql = "SELECT Name, Population FROM Country WHERE Name=?";
public void init () throws ServletException {
try {
ctx = new InitialContext();
ds = (DataSource) ctx.lookup("java:comp/env/jdbc/MySQLDataSource");
conn = ds.getConnection();
ps = conn.prepareStatement(sql);
}
catch (SQLException se) {
System.out.println("SQLException: "+se.getMessage());
}
catch (NamingException ne) {
System.out.println("NamingException: "+ne.getMessage());
}
}
public void destroy () {
try {
if (rs != null)
rs.close();
if (ps != null)
ps.close();
if (conn != null)
conn.close();
if (ctx != null)
ctx.close();
}
catch (SQLException se) {
System.out.println("SQLException: "+se.getMessage());
}
catch (NamingException ne) {
System.out.println("NamingException: "+ne.getMessage());
}
}
public void doPost(HttpServletRequest req, HttpServletResponse resp){
try {
String country_name = req.getParameter("country_name");
resp.setContentType("text/html");
PrintWriter writer = resp.getWriter();
writer.println("<html><body>");
writer.println("<p>Country: "+country_name+"</p>");
ps.setString(1, country_name);
rs = ps.executeQuery();
if (!rs.next()){
writer.println("<p>Country does not exist!</p>");
}
else {
rs.beforeFirst();
while(rs.next()) {
writer.println("<p>Name: "+rs.getString("Name")+"</p>");
writer.println("<p>Population: "+rs.getString("Population")+"</p>");
}
}
writer.println("</body></html>");
writer.close();
}
catch (Exception e) {
e.printStackTrace();
}
}
public void doGet(HttpServletRequest req, HttpServletResponse resp){
try {
resp.setContentType("text/html");
PrintWriter writer = resp.getWriter();
writer.println("<html><body>");
writer.println("<p>Hello from servlet doGet()</p>");
writer.println("</body></html>");
writer.close();
}
catch (Exception e) {
e.printStackTrace();
}
}
}
In the preceding code a basic doGet()
method is implemented, but is not used in the example. The
code to establish the connection with the database is as
shown in the previous example,
Section 5.2.5.1, “A Simple JSP Application with Glassfish, Connector/J and MySQL”,
and is most conveniently located in the servlet
init() method. The corresponding freeing
of resources is located in the destroy method. The main
functionality of the servlet is located in the
doPost() method. If the user enters nto
the input form a country name that can be located in the
database, the population of the country is returned. The
code is invoked using a POST action associated with the
input form. The form is defined in the file
index.html:
<html>
<head><title>HelloWebServlet</title></head>
<body>
<h1>HelloWebServlet</h1>
<p>Please enter country name:</p>
<form action="HelloWebServlet" method="POST">
<input type="text" name="country_name" length="50" />
<input type="submit" value="Submit" />
</form>
</body>
</html>
The XML files web.xml and
sun-web.xml are as for the example in
the preceding section,
Section 5.2.5.1, “A Simple JSP Application with Glassfish, Connector/J and MySQL”,
no additional changes are required.
Whe compiling the Java source code, you will need to specify
the path to the file javaee.jar. On
Windows, this can be done as follows:
shell> javac -classpath c:\glassfishv3\glassfish\lib\javaee.jar HelloWebServlet.java
Once the code is correctly located within its directory structure, and compiled, the application can be deployed in Glassfish. This is done in exactly the same way as described in the preceding section, Section 5.2.5.1, “A Simple JSP Application with Glassfish, Connector/J and MySQL”.
Once deployed the application can be launched from within the Glassfish Administration Console. Enter a country name such as “England”, and the application will return “Country does not exist!”. Enter “France”, and the application will return a population of 59225700.
There are a few issues that seem to be commonly encountered often by users of MySQL Connector/J. This section deals with their symptoms, and their resolutions.
Questions
5.3.1: When I try to connect to the database with MySQL Connector/J, I get the following exception:
SQLException: Server configuration denies access to data source SQLState: 08001 VendorError: 0
What is going on? I can connect just fine with the MySQL command-line client.
5.3.2: My application throws an SQLException 'No Suitable Driver'. Why is this happening?
5.3.3: I'm trying to use MySQL Connector/J in an applet or application and I get an exception similar to:
SQLException: Cannot connect to MySQL server on host:3306. Is there a MySQL server running on the machine/port you are trying to connect to? (java.security.AccessControlException) SQLState: 08S01 VendorError: 0
5.3.4: I have a servlet/application that works fine for a day, and then stops working overnight
5.3.5: I'm trying to use JDBC-2.0 updatable result sets, and I get an exception saying my result set is not updatable.
5.3.6: I cannot connect to the MySQL server using Connector/J, and I'm sure the connection paramters are correct.
5.3.7: I am trying to connect to my MySQL server within my application, but I get the following error and stack trace:
java.net.SocketException MESSAGE: Software caused connection abort: recv failed STACKTRACE: java.net.SocketException: Software caused connection abort: recv failed at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(Unknown Source) at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1392) at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1414) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:625) at com.mysql.jdbc.Connection.createNewIO(Connection.java:1926) at com.mysql.jdbc.Connection.<init>(Connection.java:452) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)
5.3.8: My application is deployed through JBoss and I am using transactions to handle the statements on the MySQL database. Under heavy loads I am getting a error and stack trace, but these only occur after a fixed period of heavy activity.
5.3.9:
When using gcj an
java.io.CharConversionException is
raised when working with certain character sequences.
5.3.10:
Updating a table that contains a primary key that is
either FLOAT or compound
primary key that uses FLOAT
fails to update the table and raises an exception.
5.3.11:
You get an
ER_NET_PACKET_TOO_LARGE
exception, even though the binary blob size you want to
insert using JDBC is safely below the
max_allowed_packet size.
5.3.12: What should you do if you receive error messages similar to the following: “Communications link failure – Last packet sent to the server was X ms ago”?
5.3.13:
Why does Connector/J not reconnect to MySQL and re-issue
the statement after a communication failure, instead of
throwing an Exception, even though I use the
autoReconnect connection string option?
5.3.14: How can I use 3-byte UTF8 with Connector/J?
5.3.15:
How can I use 4-byte UTF8, utf8mb4 with
Connector/J?
5.3.16:
Using useServerPrepStmts=false and
certain character encodings can lead to corruption when
inserting BLOBs. How can this be avoided?
Questions and Answers
5.3.1: When I try to connect to the database with MySQL Connector/J, I get the following exception:
SQLException: Server configuration denies access to data source SQLState: 08001 VendorError: 0
What is going on? I can connect just fine with the MySQL command-line client.
MySQL Connector/J must use TCP/IP sockets to connect to MySQL, as Java does not support Unix Domain Sockets. Therefore, when MySQL Connector/J connects to MySQL, the security manager in MySQL server will use its grant tables to determine whether the connection should be permitted.
You must add the necessary security credentials to the
MySQL server for this to happen, using the
GRANT statement to your
MySQL Server. See GRANT Syntax, for more
information.
Testing your connectivity with the
mysql command-line client will not
work unless you add the
--host flag, and use
something other than localhost for
the host. The mysql command-line
client will use Unix domain sockets if you use the
special host name localhost. If you
are testing connectivity to
localhost, use
127.0.0.1 as the host name instead.
Changing privileges and permissions improperly in MySQL can potentially cause your server installation to not have optimal security properties.
5.3.2: My application throws an SQLException 'No Suitable Driver'. Why is this happening?
There are three possible causes for this error:
The Connector/J driver is not in your
CLASSPATH, see
Chapter 2, Connector/J Installation.
The format of your connection URL is incorrect, or you are referencing the wrong JDBC driver.
When using DriverManager, the
jdbc.drivers system property has
not been populated with the location of the
Connector/J driver.
5.3.3: I'm trying to use MySQL Connector/J in an applet or application and I get an exception similar to:
SQLException: Cannot connect to MySQL server on host:3306. Is there a MySQL server running on the machine/port you are trying to connect to? (java.security.AccessControlException) SQLState: 08S01 VendorError: 0
Either you're running an Applet, your MySQL server has been installed with the "--skip-networking" option set, or your MySQL server has a firewall sitting in front of it.
Applets can only make network connections back to the machine that runs the web server that served the .class files for the applet. This means that MySQL must run on the same machine (or you must have some sort of port re-direction) for this to work. This also means that you will not be able to test applets from your local file system, you must always deploy them to a web server.
MySQL Connector/J can only communicate with MySQL using TCP/IP, as Java does not support Unix domain sockets. TCP/IP communication with MySQL might be affected if MySQL was started with the "--skip-networking" flag, or if it is firewalled.
If MySQL has been started with the "--skip-networking"
option set (the Debian Linux package of MySQL server does
this for example), you need to comment it out in the file
/etc/mysql/my.cnf or /etc/my.cnf. Of course your my.cnf
file might also exist in the data
directory of your MySQL server, or anywhere else
(depending on how MySQL was compiled for your system).
Binaries created by us always look in /etc/my.cnf and
[datadir]/my.cnf. If your MySQL server has been
firewalled, you will need to have the firewall configured
to allow TCP/IP connections from the host where your Java
code is running to the MySQL server on the port that MySQL
is listening to (by default, 3306).
5.3.4: I have a servlet/application that works fine for a day, and then stops working overnight
MySQL closes connections after 8 hours of inactivity. You either need to use a connection pool that handles stale connections or use the "autoReconnect" parameter (see Section 4.1, “Driver/Datasource Class Names, URL Syntax and Configuration Properties for Connector/J”).
Also, you should be catching SQLExceptions in your
application and dealing with them, rather than propagating
them all the way until your application exits, this is
just good programming practice. MySQL Connector/J will set
the SQLState (see
java.sql.SQLException.getSQLState() in
your APIDOCS) to "08S01" when it encounters
network-connectivity issues during the processing of a
query. Your application code should then attempt to
re-connect to MySQL at this point.
The following (simplistic) example shows what code that can handle these exceptions might look like:
Example 5.12. Connector/J: Example of transaction with retry logic
public void doBusinessOp() throws SQLException {
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
//
// How many times do you want to retry the transaction
// (or at least _getting_ a connection)?
//
int retryCount = 5;
boolean transactionCompleted = false;
do {
try {
conn = getConnection(); // assume getting this from a
// javax.sql.DataSource, or the
// java.sql.DriverManager
conn.setAutoCommit(false);
//
// Okay, at this point, the 'retry-ability' of the
// transaction really depends on your application logic,
// whether or not you're using autocommit (in this case
// not), and whether you're using transactional storage
// engines
//
// For this example, we'll assume that it's _not_ safe
// to retry the entire transaction, so we set retry
// count to 0 at this point
//
// If you were using exclusively transaction-safe tables,
// or your application could recover from a connection going
// bad in the middle of an operation, then you would not
// touch 'retryCount' here, and just let the loop repeat
// until retryCount == 0.
//
retryCount = 0;
stmt = conn.createStatement();
String query = "SELECT foo FROM bar ORDER BY baz";
rs = stmt.executeQuery(query);
while (rs.next()) {
}
rs.close();
rs = null;
stmt.close();
stmt = null;
conn.commit();
conn.close();
conn = null;
transactionCompleted = true;
} catch (SQLException sqlEx) {
//
// The two SQL states that are 'retry-able' are 08S01
// for a communications error, and 40001 for deadlock.
//
// Only retry if the error was due to a stale connection,
// communications problem or deadlock
//
String sqlState = sqlEx.getSQLState();
if ("08S01".equals(sqlState) || "40001".equals(sqlState)) {
retryCount--;
} else {
retryCount = 0;
}
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException sqlEx) {
// You'd probably want to log this . . .
}
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException sqlEx) {
// You'd probably want to log this as well . . .
}
}
if (conn != null) {
try {
//
// If we got here, and conn is not null, the
// transaction should be rolled back, as not
// all work has been done
try {
conn.rollback();
} finally {
conn.close();
}
} catch (SQLException sqlEx) {
//
// If we got an exception here, something
// pretty serious is going on, so we better
// pass it up the stack, rather than just
// logging it. . .
throw sqlEx;
}
}
}
} while (!transactionCompleted && (retryCount > 0));
}
Use of the autoReconnect option is not
recommended because there is no safe method of
reconnecting to the MySQL server without risking some
corruption of the connection state or database state
information. Instead, you should use a connection pool
which will enable your application to connect to the
MySQL server using an available connection from the
pool. The autoReconnect facility is
deprecated, and may be removed in a future release.
5.3.5: I'm trying to use JDBC-2.0 updatable result sets, and I get an exception saying my result set is not updatable.
Because MySQL does not have row identifiers, MySQL Connector/J can only update result sets that have come from queries on tables that have at least one primary key, the query must select every primary key and the query can only span one table (that is, no joins). This is outlined in the JDBC specification.
Note that this issue only occurs when using updatable
result sets, and is caused because Connector/J is unable
to guarantee that it can identify the correct rows within
the result set to be updated without having a unique
reference to each row. There is no requirement to have a
unique field on a table if you are using
UPDATE or
DELETE statements on a
table where you can individually specify the criteria to
be matched using a WHERE clause.
5.3.6: I cannot connect to the MySQL server using Connector/J, and I'm sure the connection paramters are correct.
Make sure that the
skip-networking option has
not been enabled on your server. Connector/J must be able
to communicate with your server over TCP/IP, named sockets
are not supported. Also ensure that you are not filtering
connections through a Firewall or other network security
system. For more information, see
Can't connect to [local] MySQL server.
5.3.7: I am trying to connect to my MySQL server within my application, but I get the following error and stack trace:
java.net.SocketException MESSAGE: Software caused connection abort: recv failed STACKTRACE: java.net.SocketException: Software caused connection abort: recv failed at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(Unknown Source) at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1392) at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1414) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:625) at com.mysql.jdbc.Connection.createNewIO(Connection.java:1926) at com.mysql.jdbc.Connection.<init>(Connection.java:452) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)
The error probably indicates that you are using a older version of the Connector/J JDBC driver (2.0.14 or 3.0.x) and you are trying to connect to a MySQL server with version 4.1x or newer. The older drivers are not compatible with 4.1 or newer of MySQL as they do not support the newer authentication mechanisms.
It is likely that the older version of the Connector/J
driver exists within your application directory or your
CLASSPATH includes the older
Connector/J package.
5.3.8: My application is deployed through JBoss and I am using transactions to handle the statements on the MySQL database. Under heavy loads I am getting a error and stack trace, but these only occur after a fixed period of heavy activity.
This is a JBoss, not Connector/J, issue and is connected to the use of transactions. Under heavy loads the time taken for transactions to complete can increase, and the error is caused because you have exceeded the predefined timeout.
You can increase the timeout value by setting the
TransactionTimeout attribute to the
TransactionManagerService within the
/conf/jboss-service.xml file
(pre-4.0.3) or
/deploy/jta-service.xml for JBoss
4.0.3 or later. See
TransactionTimeoute
within the JBoss wiki for more information.
5.3.9:
When using gcj an
java.io.CharConversionException is
raised when working with certain character sequences.
This is a known issue with gcj which
raises an exception when it reaches an unknown character
or one it cannot convert. You should add
useJvmCharsetConverters=true to your
connection string to force character conversion outside of
the gcj libraries, or try a different
JDK.
5.3.10:
Updating a table that contains a primary key that is
either FLOAT or compound
primary key that uses FLOAT
fails to update the table and raises an exception.
Connector/J adds conditions to the
WHERE clause during an
UPDATE to check the old
values of the primary key. If there is no match then
Connector/J considers this a failure condition and raises
an exception.
The problem is that rounding differences between supplied values and the values stored in the database may mean that the values never match, and hence the update fails. The issue will affect all queries, not just those from Connector/J.
To prevent this issue, use a primary key that does not use
FLOAT. If you have to use a
floating point column in your primary key use
DOUBLE or
DECIMAL types in place of
FLOAT.
5.3.11:
You get an
ER_NET_PACKET_TOO_LARGE
exception, even though the binary blob size you want to
insert using JDBC is safely below the
max_allowed_packet size.
This is because the hexEscapeBlock()
method in
com.mysql.jdbc.PreparedStatement.streamToBytes()
may almost double the size of your data.
5.3.12: What should you do if you receive error messages similar to the following: “Communications link failure – Last packet sent to the server was X ms ago”?
Generally speaking, this error suggests that the network connection has been closed. There can be several root causes:
Firewalls or routers may clamp down on idle connections (the MySQL client/server protocol does not ping).
The MySQL Server may be closing idle connections which
exceed the wait_timeout or
interactive_timeout threshold.
To help troubleshoot these issues, the following tips can be used. If a recent (5.1.13+) version of Connector/J is used, you will see an improved level of information compared to earlier versions. Older versions simply display the last time a packet was sent to the server, which is frequently 0 ms ago. This is of limited use, as it may be that a packet was just sent, while a packet from the server has not been received for several hours. Knowing the period of time since Connector/J last received a packet from the server is useful information, so if this is not displayed in your exception message, it is recommended that you update Connector/J.
Further, if the time a packet was last sent/received
exceeds the wait_timeout or
interactive_timeout threshold, this is
noted in the exception message.
Although network connections can be volatile, the following can be helpful in avoiding problems:
Ensure connections are valid when used from the
connection pool. Use a query that starts with
/* ping */ to execute a lightweight
ping instead of full query. Note, the syntax of the
ping needs to be exactly as specified here.
Minimize the duration a connection object is left idle while other application logic is executed.
Explicitly validate the connection before using it if the connection has been left idle for an extended period of time.
Ensure that wait_timeout and
interactive_timeout are set
sufficiently high.
Ensure that tcpKeepalive is
enabled.
Ensure that any configurable firewall or router timeout settings allow for the maximum expected connection idle time.
Do not expect to be able to reuse a connection without problems, if it has being lying idle for a period. If a connection is to be reused after being idle for any length of time, ensure that you explicitly test it before reusing it.
5.3.13:
Why does Connector/J not reconnect to MySQL and re-issue
the statement after a communication failure, instead of
throwing an Exception, even though I use the
autoReconnect connection string option?
There are several reasons for this. The first is transactional integrity. The MySQL Reference Manual states that “there is no safe method of reconnecting to the MySQL server without risking some corruption of the connection state or database state information”. Consider the following series of statements for example:
conn.createStatement().execute( "UPDATE checking_account SET balance = balance - 1000.00 WHERE customer='Smith'"); conn.createStatement().execute( "UPDATE savings_account SET balance = balance + 1000.00 WHERE customer='Smith'"); conn.commit();
Consider the case where the connection to the server fails
after the UPDATE to
checking_account. If no exception is
thrown, and the application never learns about the
problem, it will continue executing. However, the server
did not commit the first transaction in this case, so that
will get rolled back. But execution continues with the
next transaction, and increases the
savings_account balance by 1000. The
application did not receive an exception, so it continued
regardless, eventually committing the second transaction,
as the commit only applies to the changes made in the new
connection. Rather than a transfer taking place, a deposit
was made in this example.
Note that running with auto-commit
enabled does not solve this problem. When Connector/J
encounters a communication problem, there is no means to
determine whether the server processed the currently
executing statement or not. The following theoretical
states are equally possible:
The server never received the statement, and therefore no related processing occurred on the server.
The server received the statement, executed it in full, but the response was not received by the client.
If you are running with auto-commit
enabled, it is not possible to guarantee the state of data
on the server when a communication exception is
encountered. The statement may have reached the server, or
it may not. All you know is that communication failed at
some point, before the client received confirmation (or
data) from the server. This does not only affect
auto-commit statements though. If the
communication problem occurred during
Connection.commit(), the question
arises of whether the transaction was committed on the
server before the communication failed, or whether the
server received the commit request at all.
The second reason for the generation of exceptions is that transaction-scoped contextual data may be vulnerable, for example:
Temporary tables
User-defined variables
Server-side prepared statements
These items are lost when a connection fails, and if the connection silently reconnects without generating an exception, this could be detrimental to the correct execution of your application.
In summary, communication errors generate conditions that may well be unsafe for Connector/J to simply ignore by silently reconnecting. It is necessary for the application to be notified. It is then for the application developer to decide how to proceed in the event of connection errors and failures.
5.3.14: How can I use 3-byte UTF8 with Connector/J?
To use 3-byte UTF8 with Connector/J set
characterEncoding=utf8 and set
useUnicode=true in the connection
string.
5.3.15:
How can I use 4-byte UTF8, utf8mb4 with
Connector/J?
To use 4-byte UTF8 with Connector/J configure the MySQL
server with
character_set_server=utf8mb4.
Connector/J will then use that setting as long as
characterEncoding has not been set in
the connection string. This is equivalent to autodetection
of the character set.
5.3.16:
Using useServerPrepStmts=false and
certain character encodings can lead to corruption when
inserting BLOBs. How can this be avoided?
When using certain character encodings, such as SJIS, CP932, and BIG5, it is possible that BLOB data contains characters that can be interpreted as control characters, for example, backslash, '\'. This can lead to corrupted data when inserting BLOBs into the database. There are two things that need to be done to avoid this:
Set the connection string option
useServerPrepStmts to
true.
Set SQL_MODE to
NO_BACKSLASH_ESCAPES.
Table of Contents
Oracle provides assistance to the user community by means of its mailing lists. For Connector/J related issues, you can get help from experienced users by using the MySQL and Java mailing list. Archives and subscription information is available online at http://lists.mysql.com/java.
For information about subscribing to MySQL mailing lists or to browse list archives, visit http://lists.mysql.com/. See MySQL Mailing Lists.
Community support from experienced users is also available through the JDBC Forum. You may also find help from other users in the other MySQL Forums, located at http://forums.mysql.com. See MySQL Community Support at the MySQL Forums.
The normal place to report bugs is http://bugs.mysql.com/, which is the address for our bugs database. This database is public, and can be browsed and searched by anyone. If you log in to the system, you will also be able to enter new reports.
If you have found a sensitive security bug in MySQL, you can
send email to <security@mysql.com>.
Writing a good bug report takes patience, but doing it right the first time saves time both for us and for yourself. A good bug report, containing a full test case for the bug, makes it very likely that we will fix the bug in the next release.
This section will help you write your report correctly so that you do not waste your time doing things that may not help us much or at all.
If you have a repeatable bug report, please report it to the bugs database at http://bugs.mysql.com/. Any bug that we are able to repeat has a high chance of being fixed in the next MySQL release.
To report other problems, you can use one of the MySQL mailing lists.
Remember that it is possible for us to respond to a message containing too much information, but not to one containing too little. People often omit facts because they think they know the cause of a problem and assume that some details do not matter.
A good principle is this: If you are in doubt about stating something, state it. It is faster and less troublesome to write a couple more lines in your report than to wait longer for the answer if we must ask you to provide information that was missing from the initial report.
The most common errors made in bug reports are (a) not including the version number of Connector/J or MySQL used, and (b) not fully describing the platform on which Connector/J is installed (including the JVM version, and the platform type and version number that MySQL itself is installed on).
This is highly relevant information, and in 99 cases out of 100, the bug report is useless without it. Very often we get questions like, “Why doesn't this work for me?” Then we find that the feature requested wasn't implemented in that MySQL version, or that a bug described in a report has already been fixed in newer MySQL versions.
Sometimes the error is platform-dependent; in such cases, it is next to impossible for us to fix anything without knowing the operating system and the version number of the platform.
If at all possible, you should create a repeatable, standalone testcase that doesn't involve any third-party classes.
To streamline this process, we ship a base class for testcases
with Connector/J, named
'com.mysql.jdbc.util.BaseBugReport'. To
create a testcase for Connector/J using this class, create your
own class that inherits from
com.mysql.jdbc.util.BaseBugReport and
override the methods setUp(),
tearDown() and
runTest().
In the setUp() method, create code that
creates your tables, and populates them with any data needed to
demonstrate the bug.
In the runTest() method, create code that
demonstrates the bug using the tables and data you created in
the setUp method.
In the tearDown() method, drop any tables
you created in the setUp() method.
In any of the above three methods, you should use one of the
variants of the getConnection() method to
create a JDBC connection to MySQL:
getConnection() - Provides a connection
to the JDBC URL specified in getUrl().
If a connection already exists, that connection is returned,
otherwise a new connection is created.
getNewConnection() - Use this if you
need to get a new connection for your bug report (that is,
there is more than one connection involved).
getConnection(String url) - Returns a
connection using the given URL.
getConnection(String url, Properties
props) - Returns a connection using the given URL
and properties.
If you need to use a JDBC URL that is different from
'jdbc:mysql:///test', override the method
getUrl() as well.
Use the assertTrue(boolean expression) and
assertTrue(String failureMessage, boolean
expression) methods to create conditions that must be
met in your testcase demonstrating the behavior you are
expecting (vs. the behavior you are observing, which is why you
are most likely filing a bug report).
Finally, create a main() method that
creates a new instance of your testcase, and calls the
run method:
public static void main(String[] args) throws Exception {
new MyBugReport().run();
}Once you have finished your testcase, and have verified that it demonstrates the bug you are reporting, upload it with your bug report to http://bugs.mysql.com/.
The Connector/J Change History (Changelog) is located with the main Changelog for MySQL. See Appendix A, MySQL Connector/J Change History.
Table of Contents
Fixes bugs found since release 5.1.16.
Bugs Fixed
LIKE was not optimized in then
server when run against INFORMATION_SCHEMA
tables and no wildcards were used. Databases/tables with
'_' or '%' in their names
(escaped or not) are handled by this code path, although slower,
since it is rare to find these characters in table names in SQL.
If there is a '_' or '%'
in the string, LIKE takes care of
that; otherwise, '=' is now used instead. The
only exception is the information_schema
database, which is handled separately. The patch covers both
getTables() and
getColumns().
(Bug #61332)
The first call to a stored procedure failed with “No
Database Selected”. The workaround introduced in
DatabaseMetaData.getCallStmtParameterTypes to
fix the server bug where SHOW CREATE
PROCEDURE was not respecting lowercase table names was
misbehaving when the connection was not attached to a database
and on case-insensitive operating systems.
(Bug #61150)
There was a concurrency bottleneck in Java's character set
encoding/decoding when converting bytes to/from
String values.
No longer use String.getBytes(...), or
new String(byte[]...). Use the
StringUtils method instead.
(Bug #61105)
Fixes bugs found since release 5.1.15.
Functionality Added or Changed
The Connection.isServerLocal() method can now
determine if a connection is against a server on the same host.
Bugs Fixed
When auto-reconnect was used with
cacheServerConfiguration, errors could occur
when the host changed (in an HA setup, for example).
(Bug #12325877)
DBMD.getTables and
getColumns fail with table names that contain
a dot (like "junk_[Sp:e,c/ C-h+a=.r]"). The
workaround is to use
useInformationSchema=True.
(Bug #11782297)
Fixed a timestamp offset bug in
com.mysql.jdbc.ResultSetRow.getTimestampFast().
(Bug #60313, Bug #11890729)
wasNull was not set for a
DATE field with the value of
0000-00-00 in getDate(),
although zeroDateTimeBehavior is defined as
convertToNull.
(Bug #57808)
A bypassing of the server protocol bug, where the DB should be
null-terminated whether it exists or not. This affects
COM_CHANGE_USER.
(Bug #54425)
Fixed a bug where Connector/J would kill the matching
ConnectionID, but on the wrong server.
(Bug #54135)
Fixes bugs found since release 5.1.14.
Bugs Fixed
Optional logging class
com.mysql.jdbc.log.Log4JLogger was not
included in the source/binary package for 5.1.14.
5.1.15 will ship with an SLF4J logger (which can then be plugged into Log4J). Unfortunately, it is not possible to ship a direct Log4J integration because the GPL is not compatible with Log4J's license. (Bug #59511, Bug #11766408)
The hard-coded list of reserved words in Connector/J was not updated to reflect the list of reserved words in MySQL Server 5.5. (Bug #59224)
MySqlProcedure accepted null arguments as parameters, however the JDBC meta data did not indicate that. (Bug #38367, Bug #11749186)
Using Connector/J to connect from a z/OS machine to a MySQL Server failed when the database name to connect to was included in the connection URL. This was because the name was sent in z/OS default platform encoding, but the MySQL Server expected Latin1.
It should be noted that when connecting from systems that do not
use Latin1 as the default platform encoding, the following
connection string options can be useful:
passwordCharacterEncoding=ASCII and
characterEncoding=ASCII.
(Bug #18086, Bug #11745647)
Fixes bugs found since release 5.1.13.
Functionality Added or Changed
Connector/J's load-balancing functionality only allowed the following events to trigger failover:
Transaction commit/rollback
CommunicationExceptions
Matches to user-defined Exceptions using the loadBalanceSQLStateFailover, loadBalanceSQLExceptionSubclassFailover or loadBalanceExceptionChecker property.
This meant that connections where auto-commit was enabled were not balanced, except for Exceptions, and this was problematic in the case of distribution of read-only work across slaves in a replication deployment.
The ability to load-balance while auto-commit is enabled has now been added to Connector/J. This introduces two new properties:
loadBalanceAutoCommitStatementThreshold - defines the number of matching statements which will trigger the driver to (potentially) swap physical server connections. The default value (0) retains the previously-established behavior that connections with auto-commit enabled are never balanced.
loadBalanceAutoCommitStatementRegex - the regular expression against which statements must match. The default value (blank) matches all statements.
Load-balancing will be done after the statement is executed, before control is returned to the application. If rebalancing fails, the driver will silently swallow the resulting Exception (as the statement itself completed successfully). (Bug #55723)
Bugs Fixed
Connection failover left slave/secondary in read-only mode.
Failover attempts between two read-write masters did not
properly set
this.currentConn.setReadOnly(false).
(Bug #58706)
Connector/J mapped both 3-byte and 4-byte UTF8 encodings to the same Java UTF8 encoding.
To use 3-byte UTF8 with Connector/J set
characterEncoding=utf8 and set
useUnicode=true in the connection string.
To use 4-byte UTF8 with Connector/J configure the MySQL server
with character_set_server=utf8mb4.
Connector/J will then use that setting as long as
characterEncoding has not been set in the
connection string. This is equivalent to autodetection of the
character set.
(Bug #58232)
The CallableStatementRegression test suite
failed with a Null Pointer Exception because the
OUT parameter in the
I__S.PARAMETERS table had no name, that is
COLUMN_NAME had the value
NULL.
(Bug #58232)
DatabaseMetaData.supportsMultipleResultSets()
was hard-coded to return false, even though
Connector/J supports multiple result sets.
(Bug #57380)
Using the useOldUTF8Behavior parameter failed
to set the connection character set to latin1
as required.
In versions prior to 5.1.3, the handshake was done using
latin1, and while there was logic in place to
explicitly set the character set after the handshake was
complete, this was bypassed when
useOldUTF8Behavior was true. This was not a
problem until 5.1.3, when the handshake was modified to use
utf8, but the logic continued to allow the
character set configured during that handshake process to be
retained for later use. As a result,
useOldUTF8Behavior effectively failed.
(Bug #57262)
Invoking a stored procedure containing output parameters by its full name, where the procedure was located in another database, generated the following exception:
Parameter index of 1 is out of range (1, 0)
(Bug #57022)
When a JDBC client disconnected from a remote server using
Connection.close(), the TCP connection
remained in the TIME_WAIT state on the server
side, rather than on the client side.
(Bug #56979)
Leaving Trust/ClientCertStoreType properties unset caused an
exception to be thrown when connecting with
useSSL=true, as no default was used.
(Bug #56955)
When load-balanced connections swap servers, certain session state was copied from the previously active connection to the newly-selected connection. State synchronized included:
Auto-commit state
Transaction isolation state
Current schema/catalog
However, the read-only state was not synchronized, which caused problems if a write was attempted on a read-only connection. (Bug #56706)
When using Connector/J configured for failover (jdbc:mysql://host1,host2,... URLs), the non-primary servers re-balanced when the transactions on the master were committed or rolled-back. (Bug #56429)
An unhandled Null Pointer Exception (NPE) was generated in
DatabaseMetaData.java when calling an
incorrectly cased function name where no permission to access
mysql.proc was available.
In addition to catching potential NPEs, a guard against calling
JDBC functions with db_name.proc_name
notation was also added.
(Bug #56305)
Attempting to use JDBC4 functions on
Connection objects resulted in errors being
generated:
Exception in thread "main" java.lang.AbstractMethodError: com.mysql.jdbc.LoadBalancedMySQLConnection.createBlob()Ljava/sql/Blob; at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at com.mysql.jdbc.LoadBalancingConnectionProxy.invoke(LoadBalancingConnectionProxy.java:476) at $Proxy0.createBlob(Unknown Source)
(Bug #56099)
Fixes bugs found since release 5.1.12.
Functionality Added or Changed
Connector/J did not support utf8mb4 for
servers 5.5.2 and newer.
Connector/J now auto-detects servers configured with
character_set_server=utf8mb4 or treats the
Java encoding utf-8 passed using
characterEncoding=... as
utf8mb4 in the SET NAMES=
calls it makes when establishing the connection.
(Bug #54175)
Bugs Fixed
The method unSafeStatementInterceptors()
contained an erroneous line of code, which resulted in the
interceptor being called, but the result being thrown away.
(Bug #53041)
There was a performance regression of roughly 25% between r906 and r907, which appeared to be caused by pushing the Proxy down to the I/O layer. (Bug #52534)
Logic in implementations of
LoadBalancingConnectionProxy and
LoadBalanceStrategy behaved differently as to
which SQLExceptions trigger failover to a new
host. The former looked at the first two characters of the
SQLState:
if (sqlState.startsWith("08"))
...The latter used a different test:
if (sqlEx instanceof CommunicationsException
|| "08S01".equals(sqlEx.getSQLState())) {
...
This meant it was possible for a new
Connection object to throw an
Exception when the first selected host was
unavailable. This happened because
MySqlIO.createNewIO() could throw an
SQLException with a
SQLState of “08001”, which did
not trigger the “try another host” logic in the
LoadBalanceStrategy implementations, so an
Exception was thrown after having only
attempted connecting to a single host.
(Bug #52231)
In the file DatabaseMetadata.java, the
function private void
getCallStmtParameterTypes failed if the parameter was
defined over more than one line by using the '\n' character.
(Bug #52167)
The catalog parameter, PARAM_CAT, was not
correctly processed when calling for metadata with
getMetaData() on stored procedures. This was
because PARAM_CAT was hardcoded in the code
to NULL. In the case where
nullcatalogmeanscurrent was
true, which is its default value, a crash did
not occur, but the metadata returned was for the stored
procedures from the catalog currently attached to. If, however,
nullcatalogmeanscurrent was set to
false then a crash resulted.
Connector/J has been changed so that when
NULL is passed as
PARAM_CAT it will not crash when
nullcatalogmeanscurrent is
false, but rather iterate all catalogs in
search of stored procedures. This means that
PARAM_CAT is no longer hardcoded to
NULL (see Bug #51904).
(Bug #51912)
A load balanced Connection object with
multiple open underlying physical connections rebalanced on
commit(), rollback(), or
on a communication exception, without validating the existing
connection. This caused a problem when there was no pinging of
the physical connections, using queries starting with “/*
ping */”, to ensure they remained active. This meant that
calls to Connection.commit() could throw a
SQLException. This did not occur when the
transaction was actually committed; it occurred when the new
connection was chosen and the driver attempted to set the
auto-commit or transaction isolation state on the newly chosen
physical connection.
(Bug #51783)
The rollback() method could fail to rethrow a
SQLException if the server became unavailable
during a rollback. The errant code only rethrew when
ignoreNonTxTables was true and the exception
did not have the error code 1196,
SQLError.ER_WARNING_NOT_COMPLETE_ROLLBACK.
(Bug #51776)
When the allowMultiQueries connection string
option was set to true, a call to
Statement.executeBatch() scanned the query
for escape codes, even though
setEscapeProcessing(false) had been called
previously.
(Bug #51704)
When a StatementInterceptor was used and an
alternate ResultSet was returned from
preProcess(), the original statement was
still executed.
(Bug #51666)
Objects created by ConnectionImpl, such as
prepared statements, hold a reference to the
ConnectionImpl that created them. However,
when the load balancer picked a new connection, it did not
update the reference contained in, for example, the
PreparedStatement. This resulted in inserts
and updates being directed to invalid connections, while commits
were directed to the new connection. This resulted in silent
data loss.
(Bug #51643)
jdbc:mysql:loadbalance:// would connect to
the same host, even though
loadBalanceStrategy was set to a value of
random, and multiple hosts were specified.
(Bug #51266)
An unexpected exception when trying to register
OUT parameters in
CallableStatement.
Sometimes Connector/J was not able to register
OUT parameters for
CallableStatements.
(Bug #43576)
Fixes bugs found since release 5.1.11.
Bugs Fixed
The catalog parameter was ignored in the
DatabaseMetaData.getProcedure() method. It
returned all procedures in all databases.
(Bug #51022)
A call to DatabaseMetaData.getDriverVersion()
returned the revision as mysql-connector-java-5.1.11 (
Revision: ${svn.Revision} ). The variable
${svn.Revision} was not replaced by the SVN
revision number.
(Bug #50288)
Fixes bugs found since release 5.1.10.
Functionality Added or Changed
Replication connections, those with URLs that start with
jdbc:mysql:replication, now use a jdbc:mysql:loadbalance
connection for the slave pool. This means that it is possible to
set load balancing properties such as
loadBalanceBlacklistTimeout and
loadBalanceStrategy to choose a mechanism for
balancing the load, and failover or fault tolerance strategy for
the slave pool.
(Bug #49537)
Bugs Fixed
NullPointerException sometimes occurred in
invalidateCurrentConnection() for
load-balanced connections.
(Bug #50288)
The deleteRow method caused a full table
scan, when using an updatable cursor and a multibyte character
set.
(Bug #49745)
For pooled connections, Connector/J did not process the session
variable time_zone when set using the URL,
resulting in incorrect timestamp values being stored.
(Bug #49700)
The ExceptionInterceptor class did not
provide a Connection context.
(Bug #49607)
Ping left closed connections in the liveConnections map, causing subsequent Exceptions when that connection was used. (Bug #48605)
Using MysqlConnectionPoolDataSource with a
load-balanced URL generated exceptions of type
ClassCastException:
ClassCastException in MysqlConnectionPoolDataSource Caused by: java.lang.ClassCastException: $Proxy0 at com.mysql.jdbc.jdbc2.optional.MysqlConnectionPoolDataSource.getPooledConnection(MysqlConne ctionPoolDataSource.java:80)
java.lang.ClassCastException: $Proxy2 at com.mysql.jdbc.jdbc2.optional.StatementWrapper.executeQuery(StatementWrapper.java:744)
(Bug #48486)
The implementation for load-balanced
Connection used a proxy, which delegated
method calls, including equals() and
hashCode(), to underlying
Connection objects. This meant that
successive calls to hashCode() on the same
object potentially returned different values, if the proxy state
had changed such that it was utilizing a different underlying
connection.
(Bug #48442)
The batch rewrite functionality attempted to identify the start
of the VALUES list by looking for
“VALUES ” (with trailing space). However, valid
MySQL syntax permits VALUES to be followed by
whitespace or an opening parenthesis:
INSERT INTO tbl VALUES (1); INSERT INTO tbl VALUES(1);
Queries written with the above formats did not therefore gain the performance benefits of the batch rewrite. (Bug #48172)
A PermGen memory leaked was caused by the Connector/J statement
cancellation timer (java.util.Timer). When
the application was unloaded the cancellation timer did not
terminate, preventing the ClassLoader from being garbage
collected.
(Bug #36565)
With the connection string option
noDatetimeStringSync set to
true, and server-side prepared statements
enabled, the following exception was generated if an attempt was
made to obtain, using ResultSet.getString(),
a datetime value containing all zero components:
java.sql.SQLException: Value '0000-00-00' can not be represented as java.sql.Date
(Bug #32525)
Fixes bugs found since release 5.1.9.
Bugs Fixed
The DriverManager.getConnection() method
ignored a non-standard port if it was specified in the JDBC
connection string. Connector/J always used the standard port
3306 for connection creation. For example, if the string was
jdbc:mysql://localhost:6777, Connector/J
would attempt to connect to port 3306, rather than 6777.
(Bug #47494)
Bugs Fixed
In the class
com.mysql.jdbc.jdbc2.optional.SuspendableXAConnection,
which is used when
pinGlobalTxToPhysicalConnection=true, there
is a static map (XIDS_TO_PHYSICAL_CONNECTIONS) that tracks the
Xid with the XAConnection, however this map was not populated.
The effect was that the
SuspendableXAConnection was never pinned to
the real XA connection. Instead it created new connections on
calls to start, end,
resume, and prepare.
(Bug #46925)
When using the ON DUPLICATE KEY UPDATE functionality together with the rewriteBatchedStatements option set to true, an exception was generated when trying to execute the prepared statement:
INSERT INTO config_table (modified,id_) VALUES (?,?) ON DUPLICATE KEY UPDATE modified=?
The exception generated was:
java.sql.SQLException: Parameter index out of range (3 > number of parameters, which is 2). at com.sag.etl.job.processors.JdbcInsertProcessor.flush(JdbcInsertProcessor.java:135) ...... Caused by: java.sql.SQLException: Parameter index out of range (3 > number of parameters, which is 2). at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.PreparedStatement.checkBounds(PreparedStatement.java:3657) at com.mysql.jdbc.PreparedStatement.setInternal(PreparedStatement.java:3641) at com.mysql.jdbc.PreparedStatement.setBytesNoEscapeNoQuotes(PreparedStatement.java:3391) at com.mysql.jdbc.PreparedStatement.setOneBatchedParameterSet(PreparedStatement.java:4203) at com.mysql.jdbc.PreparedStatement.executeBatchedInserts(PreparedStatement.java:1759) at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1441) at com.sag.etl.job.processors.JdbcInsertProcessor.flush(JdbcInsertProcessor.java:131) ... 16 more
(Bug #46788)
When Connector/J encountered an error condition that caused it
to create a CommunicationsException, it tried
to build a friendly error message that helped diagnose what was
wrong. However, if there had been no network packets received
from the server, the error message contained the following
incorrect text:
The last packet successfully received from the server was 1,249,932,468,916 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago.
(Bug #46637)
The getSuperTypes method returned a result
set with incorrect names for the first two columns. The name of
the first column in the result set was expected to be
TYPE_CAT and that of the second column
TYPE_SCHEM. The method however returned the
names as TABLE_CAT and
TABLE_SCHEM for first and second column
respectively.
(Bug #44508)
SQLException for data truncation error gave the error code as 0 instead of 1265. (Bug #44324)
Calling ResultSet.deleteRow() on a table with
a primary key of type BINARY(8) silently
failed to delete the row, but only in some repeatable cases. The
generated DELETE statement generated
corrupted part of the primary key data. Specifically, one of the
bytes was changed from 0x90 to 0x9D, although the corruption
appeared to be different depending on whether the application
was run on Windows or Linux.
(Bug #43759)
Accessing result set columns by name after the result set had been closed resulted in a NullPointerException instead of a SQLException. (Bug #41484)
QueryTimeout did not work for batch
statements waiting on a locked table.
When a batch statement was issued to the server and was forced to wait because of a locked table, Connector/J only terminated the first statement in the batch when the timeout was exceeded, leaving the rest hanging. (Bug #34555)
The parseURL method in class
com.mysql.jdbc.Driver did not work as
expected. When given a URL such as
“jdbc:mysql://www.mysql.com:12345/my_database” to
parse, the property PORT_PROPERTY_KEY was
found to be null and the
HOST_PROPERTY_KEY property was found to be
“www.mysql.com:12345”.
Connector/J has been fixed so that it will now always fill in
the PORT property (using 3306 if not
specified), and the HOST property (using
localhost if not specified) when
parseURL() is called. The driver also
parses a list of hosts into HOST.n and
PORT.n properties as well as adding a
property NUM_HOSTS for the number of hosts
it has found. If a list of hosts is passed to the driver,
HOST and PORT will be
set to the values given by HOST.1 and
PORT.1 respectively. This change has
centralized and cleaned up a large section of code used to
generate lists of hosts, both for load-balanced and fault
tolerant connections and their tests.
(Bug #32216)
Attempting to delete rows using
ResultSet.deleteRow() did not delete rows
correctly.
(Bug #27431)
The setDate method silently ignored the
Calendar parameter. The code was implemented as follows:
public void setDate(int parameterIndex, java.sql.Date x, Calendar cal) throws SQLException {
setDate(parameterIndex, x);
}
From reviewing the code it was apparent that the Calendar
parameter cal was ignored.
(Bug #23584)
Bugs Fixed
The reported milliseconds since the last server packets were received/sent was incorrect by a factor of 1000. For example, the following method call:
SQLError.createLinkFailureMessageBasedOnHeuristics( (ConnectionImpl) this.conn, System.currentTimeMillis() - 1000, System.currentTimeMillis() - 2000, e, false);
returned the following string:
The last packet successfully received from the server was 2 milliseconds ago. The last packet sent successfully to the server was 1 milliseconds ago.
(Bug #45419)
Calling Connection.serverPrepareStatement()
variants that do not take result set type or concurrency
arguments returned statements that produced result sets with
incorrect defaults, namely
TYPE_SCROLL_SENSITIVE.
(Bug #45171)
The result set returned by getIndexInfo() did
not have the format defined in the JDBC API specifications. The
fourth column, DATA_TYPE, of the result set
should be of type BOOLEAN. Connector/J
however returns CHAR.
(Bug #44869)
The result set returned by getTypeInfo() did
not have the format defined in the JDBC API specifications. The
second column, DATA_TYPE, of the result set
should be of type INTEGER. Connector/J
however returns SMALLINT.
(Bug #44868)
The DEFERRABILITY column in database metadata
result sets was expected to be of type SHORT.
However, Connector/J returned it as INTEGER.
This affected the following methods:
getImportedKeys(),
getExportedKeys(),
getCrossReference().
(Bug #44867)
The result set returned by getColumns() did
not have the format defined in the JDBC API specifications. The
fifth column, DATA_TYPE, of the result set
should be of type INTEGER. Connector/J
however returns SMALLINT.
(Bug #44865)
The result set returned by
getVersionColumns() did not have the format
defined in the JDBC API specifications. The third column,
DATA_TYPE, of the result set should be of
type INTEGER. Connector/J however returns
SMALLINT.
(Bug #44863)
The result set returned by
getBestRowIdentifier() did not have the
format defined in the JDBC API specifications. The third column,
DATA_TYPE, of the result set should be of
type INTEGER. Connector/J however returns
SMALLINT.
(Bug #44862)
Connector/J contains logic to generate a message text
specifically for streaming result sets when there are
CommunicationsException exceptions generated.
However, this code was never reached.
In the CommunicationsException code:
private boolean streamingResultSetInPlay = false;
public CommunicationsException(ConnectionImpl conn, long lastPacketSentTimeMs,
long lastPacketReceivedTimeMs, Exception underlyingException) {
this.exceptionMessage = SQLError.createLinkFailureMessageBasedOnHeuristics(conn,
lastPacketSentTimeMs, lastPacketReceivedTimeMs, underlyingException,
this.streamingResultSetInPlay);
streamingResultSetInPlay was always false,
which in the following code in
SQLError.createLinkFailureMessageBasedOnHeuristics()
never being executed:
if (streamingResultSetInPlay) {
exceptionMessageBuf.append(
Messages.getString("CommunicationsException.ClientWasStreaming")); //$NON-NLS-1$
} else {
...(Bug #44588)
The
SQLError.createLinkFailureMessageBasedOnHeuristics()
method created a message text for communication link failures.
When certain conditions were met, this message included both
“last packet sent” and “last packet
received” information, but when those conditions were not
met, only “last packet sent” information was
provided.
Information about when the last packet was successfully received should be provided in all cases. (Bug #44587)
Statement.getGeneratedKeys() retained result
set instances until the statement was closed. This caused memory
leaks for long-lived statements, or statements used in tight
loops.
(Bug #44056)
Using useInformationSchema with
DatabaseMetaData.getExportedKeys() generated
the following exception:
com.mysql.jdbc.exceptions.MySQLIntegrityConstraintViolationException: Column 'REFERENCED_TABLE_NAME' in where clause is ambiguous ... at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1772) at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1923) at com.mysql.jdbc.DatabaseMetaDataUsingInfoSchema.executeMetadataQuery( DatabaseMetaDataUsingInfoSchema.java:50) at com.mysql.jdbc.DatabaseMetaDataUsingInfoSchema.getExportedKeys( DatabaseMetaDataUsingInfoSchema.java:603)
(Bug #43714)
LoadBalancingConnectionProxy.doPing() did not
have blacklist awareness.
LoadBalancingConnectionProxy implemented
doPing() to ping all underlying connections,
but it threw any exceptions it encountered during this process.
With the global blacklist enabled, it catches these exceptions, adds the host to the global blacklist, and only throws an exception if all hosts are down. (Bug #43421)
The method Statement.getGeneratedKeys() did
not return values for UNSIGNED BIGINTS with
values greater than Long.MAX_VALUE.
Unfortunately, because the server does not tell clients what
TYPE the auto increment value is, the driver cannot consistently
return BigIntegers for the result set returned from
getGeneratedKeys(), it will only return them
if the value is greater than Long.MAX_VALUE.
If your application needs this consistency, it will need to
check the class of the return value from
.getObject() on the ResultSet returned by
Statement.getGeneratedKeys() and if it is not
a BigInteger, create one based on the
java.lang.Long that is returned.
(Bug #43196)
When the MySQL Server was upgraded from 4.0 to 5.0, the Connector/J application then failed to connect to the server. This was because authentication failed when the application ran from EBCDIC platforms such as z/OS. (Bug #43071)
When connecting with traceProtocol=true, no
trace data was generated for the server greeting or login
request.
(Bug #43070)
Connector/J generated an unhandled
StringIndexOutOfBoundsException:
java.lang.StringIndexOutOfBoundsException: String index out of range: -1 at java.lang.String.substring(String.java:1938) at com.mysql.jdbc.EscapeProcessor.processTimeToken(EscapeProcessor.java:353) at com.mysql.jdbc.EscapeProcessor.escapeSQL(EscapeProcessor.java:257) at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1546) at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1524)
(Bug #42253)
A ConcurrentModificationException was
generated in LoadBalancingConnectionProxy:
java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(Unknown Source) at java.util.HashMap$KeyIterator.next(Unknown Source) at com.mysql.jdbc.LoadBalancingConnectionProxy.getGlobalBlacklist(LoadBalancingConnectionProxy.java:520) at com.mysql.jdbc.RandomBalanceStrategy.pickConnection(RandomBalanceStrategy.java:55) at com.mysql.jdbc.LoadBalancingConnectionProxy.pickNewConnection(LoadBalancingConnectionProxy.java:414) at com.mysql.jdbc.LoadBalancingConnectionProxy.invoke(LoadBalancingConnectionProxy.java:390)
(Bug #42055)
SQL injection was possible when using a string containing U+00A5 in a client-side prepared statement, and the character set being used was SJIS/Windows-31J. (Bug #41730)
If there was an apostrophe in a comment in a statement that was
being sent through Connector/J, the apostrophe was still
recognized as a quote and put the state machine in
EscapeTokenizer into the
inQuotes state. This led to further parse
errors.
For example, consider the following statement:
String sql = "-- Customer's zip code will be fixed\n" +
"update address set zip_code = 99999\n" +
"where not regexp '^[0-9]{5}([[.-.]])?([0-9]{4})?$'";
When passed through Connector/J, the
EscapeTokenizer did not recognize that the
first apostrophe was in a comment and thus set
inQuotes to true. When that happened, the
quote count was incorrect and thus the regular expression did
not appear to be in quotation marks. With the parser not
detecting that the regular expression was in quotation marks,
the curly braces were recognized as escape sequences and were
removed from the regular expression, breaking it. The server
thus received SQL such as:
-- Customer's zip code will be fixed update address set zip_code = '99999' where not regexp '^[0-9]([[.-.]])?([0-9])?$'
(Bug #41566)
MySQL Connector/J 5.1.7 was slower than previous versions when
the rewriteBatchedStatements option was set
to true.
The performance regression in
indexOfIgnoreCaseRespectMarker()has been
fixed. It has also been made possible for the driver to
rewrite INSERT statements with ON
DUPLICATE KEY UPDATE clauses in them, as long as the
UPDATE clause contains no reference to
LAST_INSERT_ID(), as that would cause the
driver to return bogus values for
getGeneratedKeys() invocations. This has
resulted in improved performance over version 5.1.7.
(Bug #41532)
When accessing a result set column by name using
ResultSetImpl.findColumn() an exception was
generated:
java.lang.NullPointerException at com.mysql.jdbc.ResultSetImpl.findColumn(ResultSetImpl.java:1103) at com.mysql.jdbc.ResultSetImpl.getShort(ResultSetImpl.java:5415) at org.apache.commons.dbcp.DelegatingResultSet.getShort(DelegatingResultSet.java:219) at com.zimbra.cs.db.DbVolume.constructVolume(DbVolume.java:297) at com.zimbra.cs.db.DbVolume.get(DbVolume.java:197) at com.zimbra.cs.db.DbVolume.create(DbVolume.java:95) at com.zimbra.cs.store.Volume.create(Volume.java:227) at com.zimbra.cs.store.Volume.create(Volume.java:189) at com.zimbra.cs.service.admin.CreateVolume.handle(CreateVolume.java:48) at com.zimbra.soap.SoapEngine.dispatchRequest(SoapEngine.java:428) at com.zimbra.soap.SoapEngine.dispatch(SoapEngine.java:285)
(Bug #41484)
The RETURN_GENERATED_KEYS flag was being
ignored. For example, in the following code the
RETURN_GENERATED_KEYS flag was ignored:
PreparedStatement ps = connection.prepareStatement("INSERT INTO table
values(?,?)",PreparedStatement.RETURN_GENERATED_KEYS);(Bug #41448)
When using Connector/J 5.1.7 to connect to MySQL Server 4.1.18 the following error message was generated:
Thu Dec 11 17:38:21 PST 2008 WARN: Invalid value {1} for server variable named {0},
falling back to sane default of {2}
This occurred with MySQL Server version that did not support
auto_increment_increment. The error message
should not have been generated.
(Bug #41416)
When DatabaseMetaData.getProcedureColumns()
was called, the value for LENGTH was always
returned as 65535, regardless of the column type (fixed or
variable) or the actual length of the column.
However, if you obtained the PRECISION value,
this was correct for both fixed and variable length columns.
(Bug #41269)
PreparedStatement.addBatch() did not check
for all parameters being set, which led to inconsistent behavior
in executeBatch(), especially when rewriting
batched statements into multi-value INSERTs.
(Bug #41161)
Error message strings contained variable values that were not expanded. For example:
Mon Nov 17 11:43:18 JST 2008 WARN: Invalid value {1} for server variable named {0},
falling back to sane default of {2}(Bug #40772)
When using rewriteBatchedStatements=true
with:
INSERT INTO table_name_values (...) VALUES (...)
Query rewriting failed because “values” at the end of the table name was mistaken for the reserved keyword. The error generated was as follows:
testBug40439(testsuite.simple.TestBug40439)java.sql.BatchUpdateException: You have an
error in your SQL syntax; check the manual that corresponds to your MySQL server version
for the right syntax to use near 'values (2,'toto',2),(id,data, ordr) values
(3,'toto',3),(id,data, ordr) values (' at line 1
at com.mysql.jdbc.PreparedStatement.executeBatchedInserts(PreparedStatement.java:1495)
at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1097)
at testsuite.simple.TestBug40439.testBug40439(TestBug40439.java:42)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at testsuite.simple.TestBug40439.main(TestBug40439.java:57)(Bug #40439)
A statement interceptor received the incorrect parameters when used with a batched statement. (Bug #39426)
Using Connector/J 5.1.6 the method
ResultSet.getObject returned a
BYTE[] for following:
SELECT TRIM(rowid) FROM tbl
Where rowid had a type of INT(11)
PRIMARY KEY AUTO_INCREMENT.
The expected return type was one of CHAR,
VARCHAR, CLOB, however, a
BYTE[] was returned.
Further, adding
functionsNeverReturnBlobs=true to the
connection string did not have any effect on the return type.
(Bug #38387)
Functionality Added or Changed
When statements include ON DUPLICATE UPDATE,
and rewriteBatchedStatements is set to true,
batched statements are not rewritten into the form
INSERT INTO table VALUES (), (), (), instead
the statements are executed sequentially.
Bugs Fixed
Statement.getGeneratedKeys() returned two
keys when using ON DUPLICATE KEY UPDATE and
the row was updated, not inserted.
(Bug #42309)
When using the replication driver with
autoReconnect=true, Connector/J checks in
PreparedStatement.execute (also called by
CallableStatement.execute) to determine if
the first character of the statement is an “S”, in
an attempt to block all statements that are not read-only-safe,
for example non-SELECT
statements. However, this also blocked
CALLs to stored procedures, even
if the stored procedures were defined as SQL READ
DATA or NO SQL.
(Bug #40031)
With large result sets ResultSet.findColumn
became a performance bottleneck.
(Bug #39962)
Connector/J ignored the value of the MySQL Server variable
auto_increment_increment.
(Bug #39956)
Connector/J failed to parse
TIMESTAMP strings for nanos
correctly.
(Bug #39911)
When the LoadBalancingConnectionProxy handles
a SQLException with SQL state starting with
“08”, it calls
invalidateCurrentConnection, which in turn
removes that Connection from
liveConnections and the
connectionsToHostsMap, but it did not add the
host to the new global blacklist, if the global blacklist was
enabled.
There was also the possibility of a
NullPointerException when trying to update
stats, where
connectionsToHostsMap.get(this.currentConn)
was called:
int hostIndex = ((Integer) this.hostsToListIndexMap.get(this.connectionsToHostsMap.get(this.currentConn))).intValue();
This could happen if a client tried to issue a rollback after
catching a SQLException caused by a
connection failure.
(Bug #39784)
When configuring the Java Replication Driver the last slave specified was never used. (Bug #39611)
When an INSERT ON DUPLICATE KEY UPDATE was
performed, and the key already existed, the
affected-rows value was returned as 1 instead
of 0.
(Bug #39352)
When using the random load balancing strategy and starting with
two servers that were both unavailable, an
IndexOutOfBoundsException was generated when
removing a server from the whiteList.
(Bug #38782)
Connector/J threw the following exception when using a read-only connection:
java.sql.SQLException: Connection is read-only. Queries leading to data modification are not allowed.
(Bug #38747)
Connector/J was unable to connect when using a
non-latin1 password.
(Bug #37570)
The useOldAliasMetadataBehavior connection
property was ignored.
(Bug #35753)
Incorrect result is returned from
isAfterLast() in streaming
ResultSet when using
setFetchSize(Integer.MIN_VALUE).
(Bug #35170)
When getGeneratedKeys() was called on a
statement that had not been created with
RETURN_GENERATED_KEYS, no exception was
thrown, and batched executions then returned erroneous values.
(Bug #34185)
The loadBalance
bestResponseTime blacklists did not have a
global state.
(Bug #33861)
Functionality Added or Changed
Multiple result sets were not supported when using streaming
mode to return data. Both normal statements and the resul sets
from stored procedures now return multiple results sets, with
the exception of result sets using registered
OUTPUT parameters.
(Bug #33678)
XAConnections and datasources have been updated to the JDBC-4.0 standard.
The profiler event handling has been made extensible using the
profilerEventHandler connection property.
Add the verifyServerCertificate property. If
set to "false" the driver will not verify the server's
certificate when useSSL is set to "true"
When using this feature, the keystore parameters should be
specified by the clientCertificateKeyStore*
properties, rather than system properties, as the JSSE doesn't
it straightforward to have a nonverifying trust store and the
"default" key store.
Bugs Fixed
DatabaseMetaData.getColumns() returns
incorrect COLUMN_SIZE value for
SET column.
(Bug #36830)
When trying to read Time values like
“00:00:00” with
ResultSet.getTime(int) an exception is
thrown.
(Bug #36051)
JDBC connection URL parameters is ignored when using
MysqlConnectionPoolDataSource.
(Bug #35810)
When useServerPrepStmts=true and slow query
logging is enabled, the connector throws a
NullPointerException when it encounters a
slow query.
(Bug #35666)
When using the keyword “loadbalance” in the connection string and trying to perform load balancing between two databases, the driver appears to hang. (Bug #35660)
JDBC data type getter method was changed to accept only column name, whereas previously it accepted column label. (Bug #35610)
Prepared statements from pooled connections caused a
NullPointerException when
closed() under JDBC-4.0.
(Bug #35489)
In calling a stored function returning a
bigint, an exception is encountered
beginning:
java.sql.SQLException: java.lang.NumberFormatException: For input string:
followed by the text of the stored function starting after the argument list. (Bug #35199)
The JDBC driver uses a different method for evaluating column
names in
resultsetmetadata.getColumnName() and
when looking for a column in
resultset.getObject(columnName). This
causes Hibernate to fail in queries where the two methods yield
different results, for example in queries that use alias names:
SELECT column AS aliasName from table
(Bug #35150)
MysqlConnectionPoolDataSource does not
support ReplicationConnection. Notice that we
implemented com.mysql.jdbc.Connection for
ReplicationConnection, however, only
accessors from ConnectionProperties are implemented (not the
mutators), and they return values from the currently active
connection. All other methods from
com.mysql.jdbc.Connection are implemented,
and operate on the currently active connection, with the
exception of resetServerState() and
changeUser().
(Bug #34937)
ResultSet.getTimestamp() returns incorrect
values for month/day of
TIMESTAMPs when using server-side
prepared statements (not enabled by default).
(Bug #34913)
RowDataStatic doesn't always set the
metadata in ResultSetRow, which can lead
to failures when unpacking DATE,
TIME,
DATETIME and
TIMESTAMP types when using
absolute, relative, and previous result set navigation methods.
(Bug #34762)
When calling isValid() on an active
connection, if the timeout is nonzero then the
Connection is invalidated even if the
Connection is valid.
(Bug #34703)
It was not possible to truncate a
BLOB using
Blog.truncate() when using 0 as an argument.
(Bug #34677)
When using a cursor fetch for a statement, the internal prepared statement could cause a memory leak until the connection was closed. The internal prepared statement is now deleted when the corresponding result set is closed. (Bug #34518)
When retrieving the column type name of a geometry field, the
driver would return UNKNOWN instead of
GEOMETRY.
(Bug #34194)
Statements with batched values do not return correct values for
getGeneratedKeys() when
rewriteBatchedStatements is set to
true, and the statement has an ON
DUPLICATE KEY UPDATE clause.
(Bug #34093)
The internal class
ResultSetInternalMethods referenced the
nonpublic class
com.mysql.jdbc.CachedResultSetMetaData.
(Bug #33823)
A NullPointerException could be raised when
using client-side prepared statements and enabled the prepared
statement cache using the cachePrepStmts.
(Bug #33734)
Using server side cursors and cursor fetch, the table metadata information would return the data type name instead of the column name. (Bug #33594)
ResultSet.getTimestamp() would throw a
NullPointerException instead of a
SQLException when called on an empty
ResultSet.
(Bug #33162)
Load balancing connection using best response time would incorrectly "stick" to hosts that were down when the connection was first created.
We solve this problem with a black list that is used during the
picking of new hosts. If the black list ends up including all
configured hosts, the driver will retry for a configurable
number of times (the retriesAllDown
configuration property, with a default of 120 times), sleeping
250ms between attempts to pick a new connection.
We've also went ahead and made the balancing strategy
extensible. To create a new strategy, implement the interface
com.mysql.jdbc.BalanceStrategy (which
also includes our standard "extension" interface), and tell the
driver to use it by passing in the class name using the
loadBalanceStrategy configuration property.
(Bug #32877)
During a Daylight Savings Time (DST) switchover, there was no way to store two timestamp/datetime values , as the hours end up being the same when sent as the literal that MySQL requires.
Note that to get this scenario to work with MySQL (since it
doesn't support per-value timezones), you need to configure your
server (or session) to be in UTC, and tell the driver not to use
the legacy date/time code by setting
useLegacyDatetimeCode to "false". This will
cause the driver to always convert to/from the server and client
timezone consistently.
This bug fix also fixes Bug #15604, by adding entirely new
date/time handling code that can be switched on by
useLegacyDatetimeCode being set to "false" as a
JDBC configuration property. For Connector/J 5.1.x, the default
is "true", in trunk and beyond it will be "false" (that is, the
old date/time handling code will be deprecated)
(Bug #32577, Bug #15604)
When unpacking rows directly, we don't hand off error message packets to the internal method which decodes them correctly, so no exception is raised, and the driver than hangs trying to read rows that aren't there. This tends to happen when calling stored procedures, as normal SELECTs won't have an error in this spot in the protocol unless an I/O error occurs. (Bug #32246)
When using a connection from
ConnectionPoolDataSource, some
Connection.prepareStatement() methods would
return null instead of the prepared statement.
(Bug #32101)
Using CallableStatement.setNull() on a
stored function would throw an
ArrayIndexOutOfBounds exception when setting
the last parameter to null.
(Bug #31823)
MysqlValidConnectionChecker doesn't
properly handle connections created using
ReplicationConnection.
(Bug #31790)
Retrieving the server version information for an active connection could return invalid information if the default character encoding on the host was not ASCII compatible. (Bug #31192)
Further fixes have been made to this bug in the event that a node is nonresponsive. Connector/J will now try a different random node instead of waiting for the node to recover before continuing. (Bug #31053)
ResultSet returned by
Statement.getGeneratedKeys() is not closed
automatically when statement that created it is closed.
(Bug #30508)
DatabaseMetadata.getColumns() doesn't
return the correct column names if the connection character
isn't UTF-8. A bug in MySQL server compounded the issue, but was
fixed within the MySQL 5.0 release cycle. The fix includes
changes to all the sections of the code that access the server
metadata.
(Bug #20491)
Fixed ResultSetMetadata.getColumnName()
for result sets returned from
Statement.getGeneratedKeys() - it was
returning null instead of "GENERATED_KEY" as in 5.0.x.
New Features, Compared to the 5.0 Series of Connector/J
JDBC-4.0 support for setting per-connection client information
(which can be viewed in the comments section of a query using
SHOW PROCESSLIST on a MySQL
server, or can be extended to support custom persistence of the
information using a public interface).
Support for JDBC-4.0 XML processing using JAXP interfaces to DOM, SAX and StAX.
JDBC-4.0 standardized unwrapping to interfaces that include vendor extensions.
Functionality Added or Changed
Added autoSlowLog configuration property,
overrides slowQueryThreshold* properties,
driver determines slow queries by those that are slower than 5 *
stddev of the mean query time (outside the 96% percentile).
Bugs Fixed
When a connection is in read-only mode, queries that are wrapped in parentheses were incorrectly identified DML statements. (Bug #28256)
When calling setTimestamp on a prepared
statement, the timezone information stored in the calendar
object was ignored. This resulted in the incorrect
DATETIME information being stored. The
following example illustrates this:
Timestamp t = new Timestamp( cal.getTimeInMillis() ); ps.setTimestamp( N, t, cal );
(Bug #15604)
Only released internally.
This section has no changelog entries.
New Features, Compared to the 5.0 Series of Connector/J
JDBC-4.0 support for setting per-connection client information
(which can be viewed in the comments section of a query using
SHOW PROCESSLIST on a MySQL
server, or can be extended to support custom persistence of the
information using a public interface).
Support for JDBC-4.0 XML processing using JAXP interfaces to DOM, SAX and StAX.
JDBC-4.0 standardized unwrapping to interfaces that include vendor extensions.
Functionality Added or Changed
Connector/J now connects using an initial character set of
utf-8 solely for the purpose of
authentication to permit user names or database names in any
character set to be used in the JDBC connection URL.
(Bug #29853)
Added two configuration parameters:
blobsAreStrings: Should the driver always
treat BLOBs as Strings. Added specifically to work around
dubious metadata returned by the server for GROUP
BY clauses. Defaults to false.
functionsNeverReturnBlobs: Should the
driver always treat data from functions returning
BLOBs as Strings. Added specifically to
work around dubious metadata returned by the server for
GROUP BY clauses. Defaults to false.
Setting rewriteBatchedStatements to
true now causes CallableStatements with
batched arguments to be re-written in the form "CALL (...); CALL
(...); ..." to send the batch in as few client/server round
trips as possible.
The driver now picks appropriate internal row representation
(whole row in one buffer, or individual byte[]s for each column
value) depending on heuristics, including whether or not the row
has BLOB or
TEXT types and the overall
row-size. The threshold for row size that will cause the driver
to use a buffer rather than individual byte[]s is configured by
the configuration property
largeRowSizeThreshold, which has a default
value of 2KB.
The data (and how it is stored) for ResultSet
rows are now behind an interface which enables us (in some
cases) to allocate less memory per row, in that for "streaming"
result sets, we re-use the packet used to read rows, since only
one row at a time is ever active.
Added experimental support for statement "interceptors" through
the com.mysql.jdbc.StatementInterceptor
interface, examples are in
com/mysql/jdbc/interceptors. Implement this
interface to be placed "in between" query execution, so that it
can be influenced (currently experimental).
The driver will automatically adjust the server session variable
net_write_timeout when it
determines its been asked for a "streaming" result, and resets
it to the previous value when the result set has been consumed.
(The configuration property is named
netTimeoutForStreamingResults, with a unit of
seconds, the value '0' means the driver will not try and adjust
this value).
JDBC-4.0 ease-of-development features including
auto-registration with the DriverManager
through the service provider mechanism, standardized Connection
validity checks and categorized SQLExceptions
based on recoverability/retry-ability and class of the
underlying error.
Statement.setQueryTimeout()s now affect the
entire batch for batched statements, rather than the individual
statements that make up the batch.
Errors encountered during
Statement/PreparedStatement/CallableStatement.executeBatch()
when rewriteBatchStatements has been set to
true now return
BatchUpdateExceptions according to the
setting of continueBatchOnError.
If continueBatchOnError is set to
true, the update counts for the "chunk" that
were sent as one unit will all be set to
EXECUTE_FAILED, but the driver will attempt
to process the remainder of the batch. You can determine which
"chunk" failed by looking at the update counts returned in the
BatchUpdateException.
If continueBatchOnError is set to "false",
the update counts returned will contain all updates up-to and
including the failed "chunk", with all counts for the failed
"chunk" set to EXECUTE_FAILED.
Since MySQL doesn't return multiple error codes for
multiple-statements, or for multi-value
INSERT/REPLACE,
it is the application's responsibility to handle determining
which item(s) in the "chunk" actually failed.
New methods on com.mysql.jdbc.Statement:
setLocalInfileInputStream() and
getLocalInfileInputStream():
setLocalInfileInputStream() sets an
InputStream instance that will be used to
send data to the MySQL server for a
LOAD DATA LOCAL
INFILE statement rather than a
FileInputStream or
URLInputStream that represents the path
given as an argument to the statement.
This stream will be read to completion upon execution of a
LOAD DATA LOCAL
INFILE statement, and will automatically be closed
by the driver, so it needs to be reset before each call to
execute*() that would cause the MySQL
server to request data to fulfill the request for
LOAD DATA LOCAL
INFILE.
If this value is set to NULL, the driver
will revert to using a FileInputStream or
URLInputStream as required.
getLocalInfileInputStream() returns the
InputStream instance that will be used to
send data in response to a
LOAD DATA LOCAL
INFILE statement.
This method returns NULL if no such
stream has been set using
setLocalInfileInputStream().
Setting useBlobToStoreUTF8OutsideBMP to
true tells the driver to treat
[MEDIUM/LONG]BLOB columns as
[LONG]VARCHAR columns holding text encoded in
UTF-8 that has characters outside the BMP (4-byte encodings),
which MySQL server can't handle natively.
Set utf8OutsideBmpExcludedColumnNamePattern to
a regex so that column names matching the given regex will still
be treated as BLOBs The regex must follow the
patterns used for the java.util.regexpackage.
The default is to exclude no columns, and include all columns.
Set utf8OutsideBmpIncludedColumnNamePattern to
specify exclusion rules to
utf8OutsideBmpExcludedColumnNamePattern". The regex must follow
the patterns used for the java.util.regex
package.
Bugs Fixed
setObject(int, Object, int, int) delegate in
PreparedStatementWrapper delegates to wrong method.
(Bug #30892)
NPE with null column values when
padCharsWithSpace is set to true.
(Bug #30851)
Collation on VARBINARY column
types would be misidentified. A fix has been added, but this fix
only works for MySQL server versions 5.0.25 and newer, since
earlier versions didn't consistently return correct metadata for
functions, and thus results from subqueries and functions were
indistinguishable from each other, leading to type-related bugs.
(Bug #30664)
An ArithmeticException or
NullPointerException would be raised when the
batch had zero members and
rewriteBatchedStatements=true when
addBatch() was never called, or
executeBatch() was called immediately after
clearBatch().
(Bug #30550)
Closing a load-balanced connection would cause a
ClassCastException.
(Bug #29852)
Connection checker for JBoss didn't use same method parameters using reflection, causing connections to always seem "bad". (Bug #29106)
DatabaseMetaData.getTypeInfo() for the types
DECIMAL and
NUMERIC will return a precision
of 254 for server versions older than 5.0.3, 64 for versions
5.0.3 to 5.0.5 and 65 for versions newer than 5.0.5.
(Bug #28972)
CallableStatement.executeBatch() doesn't work
when connection property
noAccessToProcedureBodies has been set to
true.
The fix involves changing the behavior of
noAccessToProcedureBodies,in that the driver
will now report all paramters as IN paramters
but permit callers to call registerOutParameter() on them
without throwing an exception.
(Bug #28689)
DatabaseMetaData.getColumns() doesn't contain
SCOPE_* or
IS_AUTOINCREMENT columns.
(Bug #27915)
Schema objects with identifiers other than the connection
character aren't retrieved correctly in
ResultSetMetadata.
(Bug #27867)
Connection.getServerCharacterEncoding()
doesn't work for servers with version >= 4.1.
(Bug #27182)
The automated SVN revisions in
DBMD.getDriverVersion(). The SVN revision of
the directory is now inserted into the version information
during the build.
(Bug #21116)
Specifying a "validation query" in your connection pool that starts with "/* ping */" _exactly_ will cause the driver to instead send a ping to the server and return a fake result set (much lighter weight), and when using a ReplicationConnection or a LoadBalancedConnection, will send the ping across all active connections.
This is a new Beta development release, fixing recently discovered bugs.
Functionality Added or Changed
Setting the configuration property
rewriteBatchedStatements to
true will now cause the driver to rewrite
batched prepared statements with more than 3 parameter sets in a
batch into multi-statements (separated by ";") if they are not
plain (that is, without SELECT or
ON DUPLICATE KEY UPDATE clauses)
INSERT or
REPLACE statements.
This is a new Alpha development release, adding new features and fixing recently discovered bugs.
Functionality Added or Changed
Incompatible Change:
Pulled vendor-extension methods of Connection
implementation out into an interface to support
java.sql.Wrapper functionality from
ConnectionPoolDataSource. The vendor
extensions are javadoc'd in the
com.mysql.jdbc.Connection interface.
For those looking further into the driver implementation, it is
not an API that is used for pluggability of implementations
inside our driver (which is why there are still references to
ConnectionImpl throughout the code).
We've also added server and client
prepareStatement() methods that cover all of
the variants in the JDBC API.
Connection.serverPrepare(String) has been
re-named to
Connection.serverPrepareStatement() for
consistency with
Connection.clientPrepareStatement().
Row navigation now causes any streams/readers open on the result set to be closed, as in some cases we're reading directly from a shared network packet and it will be overwritten by the "next" row.
Made it possible to retrieve prepared statement parameter
bindings (to be used in
StatementInterceptors, primarily).
Externalized the descriptions of connection properties.
The data (and how it is stored) for ResultSet
rows are now behind an interface which enables us (in some
cases) to allocate less memory per row, in that for "streaming"
result sets, we re-use the packet used to read rows, since only
one row at a time is ever active.
Similar to Connection, we pulled out vendor
extensions to Statement into an interface
named com.mysql.Statement, and moved the
Statement class into
com.mysql.StatementImpl. The two methods
(javadoc'd in com.mysql.Statement are
enableStreamingResults(), which already
existed, and disableStreamingResults() which
sets the statement instance back to the fetch size and result
set type it had before
enableStreamingResults() was called.
Driver now picks appropriate internal row representation (whole
row in one buffer, or individual byte[]s for each column value)
depending on heuristics, including whether or not the row has
BLOB or
TEXT types and the overall
row-size. The threshold for row size that will cause the driver
to use a buffer rather than individual byte[]s is configured by
the configuration property
largeRowSizeThreshold, which has a default
value of 2KB.
Added experimental support for statement "interceptors" through
the com.mysql.jdbc.StatementInterceptor
interface, examples are in
com/mysql/jdbc/interceptors.
Implement this interface to be placed "in between" query execution, so that you can influence it. (currently experimental).
StatementInterceptors are "chainable" when
configured by the user, the results returned by the "current"
interceptor will be passed on to the next on in the chain, from
left-to-right order, as specified by the user in the JDBC
configuration property statementInterceptors.
See the sources (fully javadoc'd) for
com.mysql.jdbc.StatementInterceptor for more
details until we iron out the API and get it documented in the
manual.
Setting rewriteBatchedStatements to
true now causes
CallableStatements with batched arguments to
be re-written in the form CALL (...); CALL (...);
... to send the batch in as few client/server round
trips as possible.
This is the first public alpha release of the current Connector/J 5.1 development branch, providing an insight to upcoming features. Although some of these are still under development, this release includes the following new features and changes (in comparison to the current Connector/J 5.0 production release):
Important change: Due to a number of issues with the use of server-side prepared statements, Connector/J 5.0.5 has disabled their use by default. The disabling of server-side prepared statements does not affect the operation of the connector in any way.
To enable server-side prepared statements you must add the following configuration property to your connector string:
useServerPrepStmts=true
The default value of this property is false
(that is, Connector/J does not use server-side prepared
statements).
The disabling of server-side prepared statements does not
affect the operation of the connector. However, if you use the
useTimezone=true connection option and use
client-side prepared statements (instead of server-side
prepared statements) you should also set
useSSPSCompatibleTimezoneShift=true.
Functionality Added or Changed
Refactored CommunicationsException into a
JDBC-3.0 version, and a JDBC-4.0 version (which extends
SQLRecoverableException, now that it exists).
This change means that if you were catching
com.mysql.jdbc.CommunicationsException in
your applications instead of looking at the SQLState class of
08, and are moving to Java 6 (or newer),
you need to change your imports to that exception to be
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException,
as the old class will not be instantiated for communications
link-related errors under Java 6.
Added support for JDBC-4.0 categorized
SQLExceptions.
Added support for JDBC-4.0's NCLOB, and
NCHAR/NVARCHAR
types.
com.mysql.jdbc.java6.javac: Full path to your
Java-6 javac executable
Added support for JDBC-4.0's SQLXML interfaces.
Re-worked Ant buildfile to build JDBC-4.0 classes separately, as well as support building under Eclipse (since Eclipse can't mix/match JDKs).
To build, you must set JAVA_HOME to
J2SDK-1.4.2 or Java-5, and set the following properties on your
Ant command line:
com.mysql.jdbc.java6.javac: Full path to
your Java-6 javac executable
com.mysql.jdbc.java6.rtjar: Full path to
your Java-6 rt.jar file
New feature—driver will automatically adjust session
variable net_write_timeout when
it determines it has been asked for a "streaming" result, and
resets it to the previous value when the result set has been
consumed. (configuration property is named
netTimeoutForStreamingResults value and has a
unit of seconds, the value 0 means the driver
will not try and adjust this value).
Added support for JDBC-4.0's client information. The backend
storage of information provided using
Connection.setClientInfo() and retrieved by
Connection.getClientInfo() is pluggable by
any class that implements the
com.mysql.jdbc.JDBC4ClientInfoProvider
interface and has a no-args constructor.
The implementation used by the driver is configured using the
clientInfoProvider configuration property
(with a default of value of
com.mysql.jdbc.JDBC4CommentClientInfoProvider,
an implementation which lists the client information as a
comment prepended to every query sent to the server).
This functionality is only available when using Java-6 or newer.
com.mysql.jdbc.java6.rtjar: Full path to your
Java-6 rt.jar file
Added support for JDBC-4.0's Wrapper
interface.
Functionality Added or Changed
blobsAreStrings: Should the driver always
treat BLOBs as Strings. Added specifically to work around
dubious metadata returned by the server for GROUP
BY clauses. Defaults to false.
Added two configuration parameters:
blobsAreStrings: Should the driver always
treat BLOBs as Strings. Added specifically to work around
dubious metadata returned by the server for GROUP
BY clauses. Defaults to false.
functionsNeverReturnBlobs: Should the
driver always treat data from functions returning
BLOBs as Strings. Added specifically to
work around dubious metadata returned by the server for
GROUP BY clauses. Defaults to false.
functionsNeverReturnBlobs: Should the driver
always treat data from functions returning
BLOBs as Strings. Added specifically to work
around dubious metadata returned by the server for
GROUP BY clauses. Defaults to false.
XAConnections now start in auto-commit mode (as per JDBC-4.0 specification clarification).
Driver will now fall back to sane defaults for
max_allowed_packet and
net_buffer_length if the server
reports them incorrectly (and will log this situation at
WARN level, since it is actually an error
condition).
Bugs Fixed
Connections established using URLs of the form
jdbc:mysql:loadbalance:// weren't doing
failover if they tried to connect to a MySQL server that was
down. The driver now attempts connections to the next "best"
(depending on the load balance strategy in use) server, and
continues to attempt connecting to the next "best" server every
250 milliseconds until one is found that is up and running or 5
minutes has passed.
If the driver gives up, it will throw the last-received
SQLException.
(Bug #31053)
setObject(int, Object, int, int) delegate in
PreparedStatementWrapper delegates to wrong method.
(Bug #30892)
NPE with null column values when
padCharsWithSpace is set to true.
(Bug #30851)
Collation on VARBINARY column
types would be misidentified. A fix has been added, but this fix
only works for MySQL server versions 5.0.25 and newer, since
earlier versions didn't consistently return correct metadata for
functions, and thus results from subqueries and functions were
indistinguishable from each other, leading to type-related bugs.
(Bug #30664)
An ArithmeticException or
NullPointerException would be raised when the
batch had zero members and
rewriteBatchedStatements=true when
addBatch() was never called, or
executeBatch() was called immediately after
clearBatch().
(Bug #30550)
Closing a load-balanced connection would cause a
ClassCastException.
(Bug #29852)
Connection checker for JBoss didn't use same method parameters using reflection, causing connections to always seem "bad". (Bug #29106)
DatabaseMetaData.getTypeInfo() for the types
DECIMAL and
NUMERIC will return a precision
of 254 for server versions older than 5.0.3, 64 for versions
5.0.3 to 5.0.5 and 65 for versions newer than 5.0.5.
(Bug #28972)
CallableStatement.executeBatch() doesn't work
when connection property
noAccessToProcedureBodies has been set to
true.
The fix involves changing the behavior of
noAccessToProcedureBodies,in that the driver
will now report all paramters as IN paramters
but permit callers to call registerOutParameter() on them
without throwing an exception.
(Bug #28689)
When a connection is in read-only mode, queries that are wrapped in parentheses were incorrectly identified DML statements. (Bug #28256)
UNSIGNED types not reported using
DBMD.getTypeInfo(), and capitalization of
type names is not consistent between
DBMD.getColumns(),
RSMD.getColumnTypeName() and
DBMD.getTypeInfo().
This fix also ensures that the precision of UNSIGNED
MEDIUMINT and UNSIGNED BIGINT is
reported correctly using DBMD.getColumns().
(Bug #27916)
DatabaseMetaData.getColumns() doesn't contain
SCOPE_* or
IS_AUTOINCREMENT columns.
(Bug #27915)
Schema objects with identifiers other than the connection
character aren't retrieved correctly in
ResultSetMetadata.
(Bug #27867)
Cached metadata with
PreparedStatement.execute() throws
NullPointerException.
(Bug #27412)
Connection.getServerCharacterEncoding()
doesn't work for servers with version >= 4.1.
(Bug #27182)
The automated SVN revisions in
DBMD.getDriverVersion(). The SVN revision of
the directory is now inserted into the version information
during the build.
(Bug #21116)
Specifying a "validation query" in your connection pool that starts with "/* ping */" _exactly_ will cause the driver to instead send a ping to the server and return a fake result set (much lighter weight), and when using a ReplicationConnection or a LoadBalancedConnection, will send the ping across all active connections.
Functionality Added or Changed
The driver will now automatically set
useServerPrepStmts to true
when useCursorFetch has been set to
true, since the feature requires server-side
prepared statements to function.
tcpKeepAlive - Should the driver set
SO_KEEPALIVE (default true)?
Give more information in EOFExceptions thrown out of MysqlIO (how many bytes the driver expected to read, how many it actually read, say that communications with the server were unexpectedly lost).
Driver detects when it is running in a ColdFusion MX server
(tested with version 7), and uses the configuration bundle
coldFusion, which sets
useDynamicCharsetInfo to
false (see previous entry), and sets
useLocalSessionState and autoReconnect to
true.
tcpNoDelay - Should the driver set
SO_TCP_NODELAY (disabling the Nagle Algorithm, default
true)?
Added configuration property
slowQueryThresholdNanos - if
useNanosForElapsedTime is set to
true, and this property is set to a nonzero
value the driver will use this threshold (in nanosecond units)
to determine if a query was slow, instead of using millisecond
units.
tcpRcvBuf - Should the driver set SO_RCV_BUF
to the given value? The default value of '0', means use the
platform default value for this property.
Setting useDynamicCharsetInfo to
false now causes driver to use static lookups
for collations as well (makes
ResultSetMetadata.isCaseSensitive() much more efficient, which
leads to performance increase for ColdFusion, which calls this
method for every column on every table it sees, it appears).
Added configuration properties to enable tuning of TCP/IP socket parameters:
tcpNoDelay - Should the driver set
SO_TCP_NODELAY (disabling the Nagle Algorithm, default
true)?
tcpKeepAlive - Should the driver set
SO_KEEPALIVE (default true)?
tcpRcvBuf - Should the driver set
SO_RCV_BUF to the given value? The default value of '0',
means use the platform default value for this property.
tcpSndBuf - Should the driver set
SO_SND_BUF to the given value? The default value of '0',
means use the platform default value for this property.
tcpTrafficClass - Should the driver set
traffic class or type-of-service fields? See the
documentation for java.net.Socket.setTrafficClass() for more
information.
Setting the configuration parameter
useCursorFetch to true for
MySQL-5.0+ enables the use of cursors that enable Connector/J to
save memory by fetching result set rows in chunks (where the
chunk size is set by calling setFetchSize() on a Statement or
ResultSet) by using fully-materialized cursors on the server.
tcpSndBuf - Should the driver set SO_SND_BUF
to the given value? The default value of '0', means use the
platform default value for this property.
tcpTrafficClass - Should the driver set
traffic class or type-of-service fields? See the documentation
for java.net.Socket.setTrafficClass() for more information.
Added new debugging functionality - Setting configuration
property
includeInnodbStatusInDeadlockExceptions to
true will cause the driver to append the
output of SHOW
ENGINE INNODB STATUS to deadlock-related exceptions,
which will enumerate the current locks held inside InnoDB.
Added configuration property
useNanosForElapsedTime - for
profiling/debugging functionality that measures elapsed time,
should the driver try to use nanoseconds resolution if available
(requires JDK >= 1.5)?
If useNanosForElapsedTime is set to
true, and this property is set to "0" (or
left default), then elapsed times will still be measured in
nanoseconds (if possible), but the slow query threshold will
be converted from milliseconds to nanoseconds, and thus have
an upper bound of approximately 2000 milliseconds (as that
threshold is represented as an integer, not a long).
Bugs Fixed
Don't send any file data in response to LOAD DATA LOCAL INFILE if the feature is disabled at the client side. This is to prevent a malicious server or man-in-the-middle from asking the client for data that the client is not expecting. Thanks to Jan Kneschke for discovering the exploit and Andrey "Poohie" Hristov, Konstantin Osipov and Sergei Golubchik for discussions about implications and possible fixes. (Bug #29605)
Parser in client-side prepared statements runs to end of statement, rather than end-of-line for '#' comments. Also added support for '--' single-line comments. (Bug #28956)
Parser in client-side prepared statements eats character following '/' if it is not a multi-line comment. (Bug #28851)
PreparedStatement.getMetaData() for statements containing leading one-line comments is not returned correctly.
As part of this fix, we also overhauled detection of DML for
executeQuery() and
SELECTs for
executeUpdate() in plain and prepared
statements to be aware of the same types of comments.
(Bug #28469)
Functionality Added or Changed
Added an experimental load-balanced connection designed for use
with SQL nodes in a MySQL Cluster/NDB environment (This is not
for master-slave replication. For that, we suggest you look at
ReplicationConnection or
lbpool).
If the JDBC URL starts with
jdbc:mysql:loadbalance://host-1,host-2,...host-n,
the driver will create an implementation of
java.sql.Connection that load balances
requests across a series of MySQL JDBC connections to the given
hosts, where the balancing takes place after transaction commit.
Therefore, for this to work (at all), you must use transactions, even if only reading data.
Physical connections to the given hosts will not be created until needed.
The driver will invalidate connections that it detects have had communication errors when processing a request. A new connection to the problematic host will be attempted the next time it is selected by the load balancing algorithm.
There are two choices for load balancing algorithms, which may
be specified by the loadBalanceStrategy JDBC
URL configuration property:
random: The driver will pick a random
host for each request. This tends to work better than
round-robin, as the randomness will somewhat account for
spreading loads where requests vary in response time, while
round-robin can sometimes lead to overloaded nodes if there
are variations in response times across the workload.
bestResponseTime: The driver will route
the request to the host that had the best response time for
the previous transaction.
bestResponseTime: The driver will route the
request to the host that had the best response time for the
previous transaction.
Added configuration property
padCharsWithSpace (defaults to
false). If set to true,
and a result set column has the
CHAR type and the value does not
fill the amount of characters specified in the DDL for the
column, the driver will pad the remaining characters with space
(for ANSI compliance).
When useLocalSessionState is set to
true and connected to a MySQL-5.0 or later
server, the JDBC driver will now determine whether an actual
commit or rollback
statement needs to be sent to the database when
Connection.commit() or
Connection.rollback() is called.
This is especially helpful for high-load situations with
connection pools that always call
Connection.rollback() on connection
check-in/check-out because it avoids a round-trip to the server.
Added configuration property
useDynamicCharsetInfo. If set to
false (the default), the driver will use a
per-connection cache of character set information queried from
the server when necessary, or when set to
true, use a built-in static mapping that is
more efficient, but isn't aware of custom character sets or
character sets implemented after the release of the JDBC driver.
This only affects the padCharsWithSpace
configuration property and the
ResultSetMetaData.getColumnDisplayWidth()
method.
New configuration property,
enableQueryTimeouts (default
true).
When enabled, query timeouts set with
Statement.setQueryTimeout() use a shared
java.util.Timer instance for scheduling. Even
if the timeout doesn't expire before the query is processed,
there will be memory used by the TimerTask
for the given timeout which won't be reclaimed until the time
the timeout would have expired if it hadn't been cancelled by
the driver. High-load environments might want to consider
disabling this functionality. (this configuration property is
part of the maxPerformance configuration
bundle).
Give better error message when "streaming" result sets, and the
connection gets clobbered because of exceeding
net_write_timeout on the
server.
random: The driver will pick a random host
for each request. This tends to work better than round-robin, as
the randomness will somewhat account for spreading loads where
requests vary in response time, while round-robin can sometimes
lead to overloaded nodes if there are variations in response
times across the workload.
com.mysql.jdbc.[NonRegistering]Driver now
understands URLs of the format
jdbc:mysql:replication:// and
jdbc:mysql:loadbalance:// which will create a
ReplicationConnection (exactly like when using
[NonRegistering]ReplicationDriver) and an
experimental load-balanced connection designed for use with SQL
nodes in a MySQL Cluster/NDB environment, respectively.
In an effort to simplify things, we're working on deprecating
multiple drivers, and instead specifying different core behavior
based upon JDBC URL prefixes, so watch for
[NonRegistering]ReplicationDriver to
eventually disappear, to be replaced with
com.mysql.jdbc[NonRegistering]Driver with the
new URL prefix.
Fixed issue where a failed-over connection would let an
application call setReadOnly(false), when
that call should be ignored until the connection is reconnected
to a writable master unless failoverReadOnly
had been set to false.
Driver will now use INSERT INTO ... VALUES
(DEFAULT)form of statement for updatable result sets
for ResultSet.insertRow(), rather than
pre-populating the insert row with values from
DatabaseMetaData.getColumns()(which results
in a SHOW FULL
COLUMNS on the server for every result set). If an
application requires access to the default values before
insertRow() has been called, the JDBC URL
should be configured with
populateInsertRowWithDefaultValues set to
true.
This fix specifically targets performance issues with ColdFusion and the fact that it seems to ask for updatable result sets no matter what the application does with them.
More intelligent initial packet sizes for the "shared" packets are used (512 bytes, rather than 16K), and initial packets used during handshake are now sized appropriately as to not require reallocation.
Bugs Fixed
More useful error messages are generated when the driver thinks a result set is not updatable. (Thanks to Ashley Martens for the patch). (Bug #28085)
Connection.getTransactionIsolation() uses
"SHOW VARIABLES LIKE" which is very
inefficient on MySQL-5.0+ servers.
(Bug #27655)
Fixed issue where calling getGeneratedKeys()
on a prepared statement after calling
execute() didn't always return the generated
keys (executeUpdate() worked fine however).
(Bug #27655)
CALL /* ... */
doesn't work.
As a side effect of this fix, you can now use some_proc()/*
*/ and # comments when preparing
statements using client-side prepared statement emulation.
If the comments happen to contain parameter markers
(?), they will be treated as belonging to the
comment (that is, not recognized) rather than being a parameter
of the statement.
The statement when sent to the server will contain the
comments as-is, they're not stripped during the process of
preparing the PreparedStatement or
CallableStatement.
(Bug #27400)
ResultSet.get*() with a column index < 1
returns misleading error message.
(Bug #27317)
Using ResultSet.get*() with a column index
less than 1 returns a misleading error message.
(Bug #27317)
Comments in DDL of stored procedures/functions confuse procedure parser, and thus metadata about them can not be created, leading to inability to retrieve said metadata, or execute procedures that have certain comments in them. (Bug #26959)
Fast date/time parsing doesn't take into account
00:00:00 as a legal value.
(Bug #26789)
PreparedStatement is not closed in
BlobFromLocator.getBytes().
(Bug #26592)
When the configuration property
useCursorFetch was set to
true, sometimes server would return new, more
exact metadata during the execution of the server-side prepared
statement that enables this functionality, which the driver
ignored (using the original metadata returned during
prepare()), causing corrupt reading of data
due to type mismatch when the actual rows were returned.
(Bug #26173)
CallableStatements with
OUT/INOUT parameters that are "binary"
(BLOB,
BIT,
(VAR)BINARY, JAVA_OBJECT)
have extra 7 bytes.
(Bug #25715)
Whitespace surrounding storage/size specifiers in stored
procedure parameters declaration causes
NumberFormatException to be thrown when
calling stored procedure on JDK-1.5 or newer, as the Number
classes in JDK-1.5+ are whitespace intolerant.
(Bug #25624)
Client options not sent correctly when using SSL, leading to stored procedures not being able to return results. Thanks to Don Cohen for the bug report, testcase and patch. (Bug #25545)
Statement.setMaxRows() is not effective on
result sets materialized from cursors.
(Bug #25517)
BIT(> 1) is returned as
java.lang.String from
ResultSet.getObject() rather than
byte[].
(Bug #25328)
Functionality Added or Changed
Usage Advisor will now issue warnings for result sets with large
numbers of rows. You can configure the trigger value by using
the resultSetSizeThreshold parameter, which
has a default value of 100.
The rewriteBatchedStatements feature can now
be used with server-side prepared statements.
Important change: Due to a number of issues with the use of server-side prepared statements, Connector/J 5.0.5 has disabled their use by default. The disabling of server-side prepared statements does not affect the operation of the connector in any way.
To enable server-side prepared statements you must add the following configuration property to your connector string:
useServerPrepStmts=true
The default value of this property is false
(that is, Connector/J does not use server-side prepared
statements).
Improved speed of datetime parsing for
ResultSets that come from plain or nonserver-side prepared
statements. You can enable old implementation with
useFastDateParsing=false as a configuration
parameter.
Usage Advisor now detects empty results sets and does not report on columns not referenced in those empty sets.
Fixed logging of XA commands sent to server, it is now
configurable using logXaCommands property
(defaults to false).
Added configuration property
localSocketAddress, which is the host name or
IP address given to explicitly configure the interface that the
driver will bind the client side of the TCP/IP connection to
when connecting.
We've added a new configuration option
treatUtilDateAsTimestamp, which is
false by default, as (1) We already had
specific behavior to treat java.util.Date as a
java.sql.Timestamp because it is useful to many folks, and (2)
that behavior will very likely be required for drivers
JDBC-post-4.0.
Bugs Fixed
Connection property socketFactory wasn't
exposed using correctly named mutator/accessor, causing data
source implementations that use JavaBean naming conventions to
set properties to fail to set the property (and in the case of
SJAS, fail silently when trying to set this parameter).
(Bug #26326)
A query execution which timed out did not always throw a
MySQLTimeoutException.
(Bug #25836)
Storing a java.util.Date object in a
BLOB column would not be
serialized correctly during setObject.
(Bug #25787)
Timer instance used for
Statement.setQueryTimeout() created
per-connection, rather than per-VM, causing memory leak.
(Bug #25514)
EscapeProcessor gets confused by multiple
backslashes. We now push the responsibility of syntax errors
back on to the server for most escape sequences.
(Bug #25399)
INOUT parameters in
CallableStatements get doubly-escaped.
(Bug #25379)
When using the rewriteBatchedStatements
connection option with
PreparedState.executeBatch() an internal
memory leak would occur.
(Bug #25073)
Fixed issue where field-level for metadata from
DatabaseMetaData when using
INFORMATION_SCHEMA didn't have references to
current connections, sometimes leading to Null Pointer
Exceptions (NPEs) when introspecting them using
ResultSetMetaData.
(Bug #25073)
StringUtils.indexOfIgnoreCaseRespectQuotes()
isn't case-insensitive on the first character of the target.
This bug also affected
rewriteBatchedStatements functionality when
prepared statements did not use uppercase for the
VALUES clause.
(Bug #25047)
Client-side prepared statement parser gets confused by in-line
comments /*...*/ and therefore cannot rewrite
batch statements or reliably detect the type of statements when
they are used.
(Bug #25025)
Results sets from UPDATE
statements that are part of multi-statement queries would cause
an SQLException error, "Result is from
UPDATE".
(Bug #25009)
Specifying US-ASCII as the character set in a
connection to a MySQL 4.1 or newer server does not map
correctly.
(Bug #24840)
Using DatabaseMetaData.getSQLKeywords() does
not return a all of the of the reserved keywords for the current
MySQL version. Current implementation returns the list of
reserved words for MySQL 5.1, and does not distinguish between
versions.
(Bug #24794)
Calling Statement.cancel() could result in a
Null Pointer Exception (NPE).
(Bug #24721)
Using setFetchSize() breaks prepared
SHOW and other commands.
(Bug #24360)
Calendars and timezones are now lazily instantiated when required. (Bug #24351)
Using DATETIME columns would
result in time shifts when useServerPrepStmts
was true. This occurred due to different behavior when using
client-side compared to server-side prepared statements and the
useJDBCCompliantTimezoneShift option. This is
now fixed if moving from server-side prepared statements to
client-side prepared statements by setting
useSSPSCompatibleTimezoneShift to
true, as the driver can't tell if this is a
new deployment that never used server-side prepared statements,
or if it is an existing deployment that is switching to
client-side prepared statements from server-side prepared
statements.
(Bug #24344)
Connector/J now returns a better error message when server doesn't return enough information to determine stored procedure/function parameter types. (Bug #24065)
A connection error would occur when connecting to a MySQL server
with certain character sets. Some collations/character sets
reported as "unknown" (specifically cias
variants of existing character sets), and inability to override
the detected server character set.
(Bug #23645)
Inconsistency between getSchemas and
INFORMATION_SCHEMA.
(Bug #23304)
DatabaseMetaData.getSchemas() doesn't return
a TABLE_CATALOG column.
(Bug #23303)
When using a JDBC connection URL that is malformed, the
NonRegisteringDriver.getPropertyInfo method
will throw a Null Pointer Exception (NPE).
(Bug #22628)
Some exceptions thrown out of
StandardSocketFactory were needlessly
wrapped, obscuring their true cause, especially when using
socket timeouts.
(Bug #21480)
When using a server-side prepared statement the driver would send timestamps to the server using nanoseconds instead of milliseconds. (Bug #21438)
When using server-side prepared statements and timestamp columns, value would be incorrectly populated (with nanoseconds, not microseconds). (Bug #21438)
ParameterMetaData throws
NullPointerException when prepared SQL has a
syntax error. Added
generateSimpleParameterMetadata configuration
property, which when set to true will
generate metadata reflecting
VARCHAR for every parameter (the
default is false, which will cause an
exception to be thrown if no parameter metadata for the
statement is actually available).
(Bug #21267)
Fixed an issue where XADataSources couldn't
be bound into JNDI, as the DataSourceFactory
didn't know how to create instances of them.
Other Changes
Avoid static synchronized code in JVM class libraries for dealing with default timezones.
Performance enhancement of initial character set configuration, driver will only send commands required to configure connection character set session variables if the current values on the server do not match what is required.
Re-worked stored procedure parameter parser to be more robust.
Driver no longer requires BEGIN in stored
procedure definition, but does have requirement that if a stored
function begins with a label directly after the "returns"
clause, that the label is not a quoted identifier.
Throw exceptions encountered during timeout to thread calling
Statement.execute*(), rather than
RuntimeException.
Changed cached result set metadata (when using
cacheResultSetMetadata=true) to be cached
per-connection rather than per-statement as previously
implemented.
Reverted back to internal character conversion routines for single-byte character sets, as the ones internal to the JVM are using much more CPU time than our internal implementation.
When extracting foreign key information from
SHOW CREATE TABLE in
DatabaseMetaData, ignore exceptions relating
to tables being missing (which could happen for cross-reference
or imported-key requests, as the list of tables is generated
first, then iterated).
Fixed some Null Pointer Exceptions (NPEs) when cached metadata
was used with UpdatableResultSets.
Take localSocketAddress property into account
when creating instances of
CommunicationsException when the underlying
exception is a java.net.BindException, so
that a friendlier error message is given with a little internal
diagnostics.
Fixed cases where ServerPreparedStatements
weren't using cached metadata when
cacheResultSetMetadata=true was used.
Use a java.util.TreeMap to map column names
to ordinal indexes for ResultSet.findColumn()
instead of a HashMap. This enables us to have case-insensitive
lookups (required by the JDBC specification) without resorting
to the many transient object instances needed to support this
requirement with a normal HashMap with either
case-adjusted keys, or case-insensitive keys. (In the worst case
scenario for lookups of a 1000 column result set, TreeMaps are
about half as fast wall-clock time as a HashMap, however in
normal applications their use gives many orders of magnitude
reduction in transient object instance creation which pays off
later for CPU usage in garbage collection).
When using cached metadata, skip field-level metadata packets
coming from the server, rather than reading them and discarding
them without creating com.mysql.jdbc.Field
instances.
Bugs Fixed
DBMD.getColumns() does not return expected COLUMN_SIZE for the SET type, now returns length of largest possible set disregarding whitespace or the "," delimitters to be consistent with the ODBC driver. (Bug #22613)
Added new _ci collations to CharsetMapping - utf8_unicode_ci not working. (Bug #22456)
Driver was using milliseconds for Statement.setQueryTimeout() when specification says argument is to be in seconds. (Bug #22359)
Workaround for server crash when calling stored procedures using a server-side prepared statement (driver now detects prepare(stored procedure) and substitutes client-side prepared statement). (Bug #22297)
Driver issues truncation on write exception when it shouldn't (due to sending big decimal incorrectly to server with server-side prepared statement). (Bug #22290)
Newlines causing whitespace to span confuse procedure parser when getting parameter metadata for stored procedures. (Bug #22024)
When using information_schema for metadata, COLUMN_SIZE for getColumns() is not clamped to range of java.lang.Integer as is the case when not using information_schema, thus leading to a truncation exception that isn't present when not using information_schema. (Bug #21544)
Column names don't match metadata in cases where server doesn't
return original column names (column functions) thus breaking
compatibility with applications that expect 1-to-1 mappings
between findColumn() and
rsmd.getColumnName(), usually manifests
itself as "Can't find column ('')" exceptions.
(Bug #21379)
Driver now sends numeric 1 or 0 for client-prepared statement
setBoolean() calls instead of '1' or '0'.
Fixed configuration property
jdbcCompliantTruncation was not being used
for reads of result set values.
DatabaseMetaData correctly reports true for
supportsCatalog*() methods.
Driver now supports {call sp} (without "()"
if procedure has no arguments).
Functionality Added or Changed
Added configuration option
noAccessToProcedureBodies which will cause
the driver to create basic parameter metadata for
CallableStatements when the user does not
have access to procedure bodies using SHOW
CREATE PROCEDURE or selecting from
mysql.proc instead of throwing an exception.
The default value for this option is false
Bugs Fixed
Fixed Statement.cancel() causes
NullPointerException if underlying connection
has been closed due to server failure.
(Bug #20650)
If the connection to the server has been closed due to a server
failure, then the cleanup process will call
Statement.cancel(), triggering a
NullPointerException, even though there is no
active connection.
(Bug #20650)
Bugs Fixed
MysqlXaConnection.recover(int flags) now
permits combinations of
XAResource.TMSTARTRSCAN and
TMENDRSCAN. To simulate the
“scanning” nature of the interface, we return all
prepared XIDs for TMSTARTRSCAN, and no new
XIDs for calls with TMNOFLAGS, or
TMENDRSCAN when not in combination with
TMSTARTRSCAN. This change was made for API
compliance, as well as integration with IBM WebSphere's
transaction manager.
(Bug #20242)
Fixed MysqlValidConnectionChecker for JBoss
doesn't work with MySQLXADataSources.
(Bug #20242)
Added connection/datasource property
pinGlobalTxToPhysicalConnection (defaults to
false). When set to true,
when using XAConnections, the driver ensures
that operations on a given XID are always routed to the same
physical connection. This enables the
XAConnection to support XA START ...
JOIN after
XA END
has been called, and is also a workaround for transaction
managers that don't maintain thread affinity for a global
transaction (most either always maintain thread affinity, or
have it as a configuration option).
(Bug #20242)
Better caching of character set converters (per-connection) to remove a bottleneck for multibyte character sets. (Bug #20242)
Fixed ConnectionProperties (and thus some
subclasses) are not serializable, even though some J2EE
containers expect them to be.
(Bug #19169)
Fixed driver fails on non-ASCII platforms. The driver was
assuming that the platform character set would be a superset of
MySQL's latin1 when doing the handshake for
authentication, and when reading error messages. We now use
Cp1252 for all strings sent to the server during the handshake
phase, and a hard-coded mapping of the
language system variable to the
character set that is used for error messages.
(Bug #18086)
Fixed can't use XAConnection for local
transactions when no global transaction is in progress.
(Bug #17401)
Not released due to a packaging error
This section has no changelog entries.
Bugs Fixed
Added support for Connector/MXJ integration using url
subprotocol jdbc:mysql:mxj://....
(Bug #14729)
Idle timeouts cause XAConnections to whine
about rolling themselves back.
(Bug #14729)
When fix for Bug #14562 was merged from 3.1.12, added
functionality for CallableStatement's
parameter metadata to return correct information for
.getParameterClassName().
(Bug #14729)
Added service-provider entry to
META-INF/services/java.sql.Driver for
JDBC-4.0 support.
(Bug #14729)
Fuller synchronization of Connection to avoid
deadlocks when using multithreaded frameworks that multithread a
single connection (usually not recommended, but the JDBC spec
permits it anyways), part of fix to Bug #14972).
(Bug #14729)
Moved all SQLException constructor usage to a
factory in SQLError (ground-work for JDBC-4.0
SQLState-based exception classes).
(Bug #14729)
Removed Java5-specific calls to BigDecimal
constructor (when result set value is '',
(int)0 was being used as an argument
indirectly using method return value. This signature doesn't
exist prior to Java5.)
(Bug #14729)
Implementation of Statement.cancel() and
Statement.setQueryTimeout(). Both require
MySQL-5.0.0 or newer server, require a separate connection to
issue the KILL
QUERY statement, and in the case of
setQueryTimeout() creates an additional
thread to handle the timeout functionality.
Note: Failures to cancel the statement for
setQueryTimeout() may manifest themselves as
RuntimeExceptions rather than failing
silently, as there is currently no way to unblock the thread
that is executing the query being cancelled due to timeout
expiration and have it throw the exception instead.
(Bug #14729)
Return "[VAR]BINARY" for
RSMD.getColumnTypeName() when that is
actually the type, and it can be distinguished (MySQL-4.1 and
newer).
(Bug #14729)
Attempt detection of the MySQL type
BINARY (it is an alias, so this
isn't always reliable), and use the
java.sql.Types.BINARY type mapping for it.
Added unit tests for XADatasource, as well as
friendlier exceptions for XA failures compared to the "stock"
XAException (which has no messages).
If the connection useTimezone is set to
true, then also respect time zone conversions
in escape-processed string literals (for example, "{ts
...}" and "{t ...}").
Do not permit .setAutoCommit(true), or
.commit() or .rollback()
on an XA-managed connection as per the JDBC specification.
XADataSource implemented (ported from 3.2
branch which won't be released as a product). Use
com.mysql.jdbc.jdbc2.optional.MysqlXADataSource
as your datasource class name in your application server to
utilize XA transactions in MySQL-5.0.10 and newer.
Moved -bin-g.jar file into separate
debug subdirectory to avoid confusion.
Return original column name for
RSMD.getColumnName() if the column was
aliased, alias name for .getColumnLabel() (if
aliased), and original table name for
.getTableName(). Note this only works for
MySQL-4.1 and newer, as older servers don't make this
information available to clients.
Setting useJDBCCompliantTimezoneShift=true
(it is not the default) causes the driver to use GMT for
all
TIMESTAMP/DATETIME
time zones, and the current VM time zone for any other type that
refers to time zones. This feature can not be used when
useTimezone=true to convert between server
and client time zones.
PreparedStatement.setString() didn't work
correctly when sql_mode on
server contained
NO_BACKSLASH_ESCAPES and no
characters that needed escaping were present in the string.
Add one level of indirection of internal representation of
CallableStatement parameter metadata to avoid
class not found issues on JDK-1.3 for
ParameterMetadata interface (which doesn't
exist prior to JDBC-3.0).
Important change: Due to a number of issues with the use of server-side prepared statements, Connector/J 5.0.5 has disabled their use by default. The disabling of server-side prepared statements does not affect the operation of the connector in any way.
To enable server-side prepared statements you must add the following configuration property to your connector string:
useServerPrepStmts=true
The default value of this property is false
(that is, Connector/J does not use server-side prepared
statements).
Bugs Fixed
Specifying US-ASCII as the character set in a
connection to a MySQL 4.1 or newer server does not map
correctly.
(Bug #24840)
Bugs Fixed
Check and store value for continueBatchOnError property in constructor of Statements, rather than when executing batches, so that Connections closed out from underneath statements don't cause NullPointerExceptions when it is required to check this property. (Bug #22290)
Driver now sends numeric 1 or 0 for client-prepared statement setBoolean() calls instead of '1' or '0'. (Bug #22290)
Fixed bug where driver would not advance to next host if roundRobinLoadBalance=true and the last host in the list is down. (Bug #22290)
Driver issues truncation on write exception when it shouldn't (due to sending big decimal incorrectly to server with server-side prepared statement). (Bug #22290)
Fixed bug when calling stored functions, where parameters weren't numbered correctly (first parameter is now the return value, subsequent parameters if specified start at index "2"). (Bug #22290)
Removed logger autodetection altogether, must now specify logger explicitly if you want to use a logger other than one that logs to STDERR. (Bug #21207)
DDriver throws NPE when tracing prepared statements that have been closed (in asSQL()). (Bug #21207)
ResultSet.getSomeInteger() doesn't work for BIT(>1). (Bug #21062)
Escape of quotation marks in client-side prepared statements parsing not respected. Patch covers more than bug report, including NO_BACKSLASH_ESCAPES being set, and stacked quote characters forms of escaping (that is, '' or ""). (Bug #20888)
Fixed can't pool server-side prepared statements, exception raised when re-using them. (Bug #20687)
Fixed Updatable result set that contains a BIT column fails when server-side prepared statements are used. (Bug #20485)
Fixed updatable result set throws ClassCastException when there is row data and moveToInsertRow() is called. (Bug #20479)
Fixed ResultSet.getShort() for UNSIGNED TINYINT returns incorrect values when using server-side prepared statements. (Bug #20306)
ReplicationDriver does not always round-robin load balance depending on URL used for slaves list. (Bug #19993)
Fixed calling toString() on ResultSetMetaData for driver-generated (that is, from DatabaseMetaData method calls, or from getGeneratedKeys()) result sets would raise a NullPointerException. (Bug #19993)
Connection fails to localhost when using timeout and IPv6 is configured. (Bug #19726)
ResultSet.getFloatFromString() can't retrieve values near Float.MIN/MAX_VALUE. (Bug #18880)
DatabaseMetaData.getTables() or
getColumns() with a bad catalog parameter
threw an exception rather than return an empty result set (as
required by the specification).
(Bug #18258)
Fixed memory leak with profileSQL=true. (Bug #16987)
Fixed NullPointerException in MysqlDataSourceFactory due to Reference containing RefAddrs with null content. (Bug #16791)
Bugs Fixed
Fixed PreparedStatement.setObject(int, Object,
int) doesn't respect scale of BigDecimals.
(Bug #19615)
Fixed ResultSet.wasNull() returns incorrect
value when extracting native string from server-side prepared
statement generated result set.
(Bug #19282)
Fixed invalid classname returned for
ResultSetMetaData.getColumnClassName() for
BIGINT type.
(Bug #19282)
Fixed case where driver wasn't reading server status correctly when fetching server-side prepared statement rows, which in some cases could cause warning counts to be off, or multiple result sets to not be read off the wire. (Bug #19282)
Fixed data truncation and getWarnings() only
returns last warning in set.
(Bug #18740)
Fixed aliased column names where length of name > 251 are corrupted. (Bug #18554)
Improved performance of retrieving
BigDecimal, Time,
Timestamp and Date values
from server-side prepared statements by creating fewer
short-lived instances of Strings when the
native type is not an exact match for the requested type.
(Bug #18496)
Added performance feature, re-writing of batched executes for
Statement.executeBatch() (for all DML
statements) and
PreparedStatement.executeBatch() (for INSERTs
with VALUE clauses only). Enable by using
"rewriteBatchedStatements=true" in your JDBC URL.
(Bug #18041)
Fixed issue where server-side prepared statements don't cause truncation exceptions to be thrown when truncation happens. (Bug #18041)
Fixed
CallableStatement.registerOutParameter() not
working when some parameters pre-populated. Still waiting for
feedback from JDBC experts group to determine what correct
parameter count from getMetaData() should be,
however.
(Bug #17898)
Fixed calling clearParameters() on a closed
prepared statement causes NPE.
(Bug #17587)
Map "latin1" on MySQL server to CP1252 for MySQL > 4.1.0. (Bug #17587)
Added additional accessor and mutator methods on ConnectionProperties so that DataSource users can use same naming as regular URL properties. (Bug #17587)
Fixed ResultSet.wasNull() not always reset
correctly for booleans when done using conversion for
server-side prepared statements.
(Bug #17450)
Fixed Statement.getGeneratedKeys() throws
NullPointerException when no query has been
processed.
(Bug #17099)
Fixed updatable result set doesn't return
AUTO_INCREMENT values for
insertRow() when multiple column primary keys
are used. (the driver was checking for the existence of
single-column primary keys and an autoincrement value > 0
instead of a straightforward
isAutoIncrement() check).
(Bug #16841)
DBMD.getColumns() returns wrong type for
BIT.
(Bug #15854)
lib-nodist directory missing from package
breaks out-of-box build.
(Bug #15676)
Fixed issue with ReplicationConnection
incorrectly copying state, doesn't transfer connection context
correctly when transitioning between the same read-only states.
(Bug #15570)
No "dos" character set in MySQL > 4.1.0. (Bug #15544)
INOUT parameter does not store
IN value.
(Bug #15464)
PreparedStatement.setObject() serializes
BigInteger as object, rather than sending as
numeric value (and is thus not complementary to
.getObject() on an UNSIGNED
LONG type).
(Bug #15383)
Fixed issue where driver was unable to initialize character set
mapping tables. Removed reliance on
.properties files to hold this information,
as it turns out to be too problematic to code around class
loader hierarchies that change depending on how an application
is deployed. Moved information back into the
CharsetMapping class.
(Bug #14938)
Exception thrown for new decimal type when using updatable result sets. (Bug #14609)
Driver now aware of fix for BIT
type metadata that went into MySQL-5.0.21 for server not
reporting length consistently .
(Bug #13601)
Added support for Apache Commons logging, use "com.mysql.jdbc.log.CommonsLogger" as the value for the "logger" configuration property. (Bug #13469)
Fixed driver trying to call methods that don't exist on older and newer versions of Log4j. The fix is not trying to auto-detect presence of log4j, too many different incompatible versions out there in the wild to do this reliably.
If you relied on autodetection before, you will need to add "logger=com.mysql.jdbc.log.Log4JLogger" to your JDBC URL to enable Log4J usage, or alternatively use the new "CommonsLogger" class to take care of this. (Bug #13469)
LogFactory now prepends com.mysql.jdbc.log to
the log class name if it cannot be found as specified. This
enables you to use “short names” for the built-in
log factories, for example,
logger=CommonsLogger instead of
logger=com.mysql.jdbc.log.CommonsLogger.
(Bug #13469)
ResultSet.getShort() for UNSIGNED
TINYINT returned wrong values.
(Bug #11874)
Bugs Fixed
Process escape tokens in
Connection.prepareStatement(...). You can
disable this behavior by setting the JDBC URL configuration
property processEscapeCodesForPrepStmts to
false.
(Bug #15141)
Usage advisor complains about unreferenced columns, even though they've been referenced. (Bug #15065)
Driver incorrectly closes streams passed as arguments to
PreparedStatements. Reverts to legacy
behavior by setting the JDBC configuration property
autoClosePStmtStreams to
true (also included in the 3-0-Compat
configuration “bundle”).
(Bug #15024)
Deadlock while closing server-side prepared statements from multiple threads sharing one connection. (Bug #14972)
Unable to initialize character set mapping tables (due to J2EE classloader differences). (Bug #14938)
Escape processor replaces quote character in quoted string with string delimiter. (Bug #14909)
DatabaseMetaData.getColumns() doesn't return
TABLE_NAME correctly.
(Bug #14815)
storesMixedCaseIdentifiers() returns
false
(Bug #14562)
storesLowerCaseIdentifiers() returns
true
(Bug #14562)
storesMixedCaseQuotedIdentifiers() returns
false
(Bug #14562)
storesMixedCaseQuotedIdentifiers() returns
true
(Bug #14562)
If lower_case_table_names=0 (on server):
storesLowerCaseIdentifiers() returns
false
storesLowerCaseQuotedIdentifiers()
returns false
storesMixedCaseIdentifiers() returns
true
storesMixedCaseQuotedIdentifiers()
returns true
storesUpperCaseIdentifiers() returns
false
storesUpperCaseQuotedIdentifiers()
returns true
(Bug #14562)
storesUpperCaseIdentifiers() returns
false
(Bug #14562)
storesUpperCaseQuotedIdentifiers() returns
true
(Bug #14562)
If lower_case_table_names=1 (on server):
storesLowerCaseIdentifiers() returns
true
storesLowerCaseQuotedIdentifiers()
returns true
storesMixedCaseIdentifiers() returns
false
storesMixedCaseQuotedIdentifiers()
returns false
storesUpperCaseIdentifiers() returns
false
storesUpperCaseQuotedIdentifiers()
returns true
(Bug #14562)
storesLowerCaseQuotedIdentifiers() returns
true
(Bug #14562)
Fixed DatabaseMetaData.stores*Identifiers():
If lower_case_table_names=0 (on server):
storesLowerCaseIdentifiers() returns
false
storesLowerCaseQuotedIdentifiers()
returns false
storesMixedCaseIdentifiers() returns
true
storesMixedCaseQuotedIdentifiers()
returns true
storesUpperCaseIdentifiers() returns
false
storesUpperCaseQuotedIdentifiers()
returns true
If lower_case_table_names=1 (on server):
storesLowerCaseIdentifiers() returns
true
storesLowerCaseQuotedIdentifiers()
returns true
storesMixedCaseIdentifiers() returns
false
storesMixedCaseQuotedIdentifiers()
returns false
storesUpperCaseIdentifiers() returns
false
storesUpperCaseQuotedIdentifiers()
returns true
(Bug #14562)
storesMixedCaseIdentifiers() returns
true
(Bug #14562)
storesLowerCaseQuotedIdentifiers() returns
false
(Bug #14562)
Java type conversion may be incorrect for
MEDIUMINT.
(Bug #14562)
storesLowerCaseIdentifiers() returns
false
(Bug #14562)
Added configuration property
useGmtMillisForDatetimes which when set to
true causes
ResultSet.getDate(),
.getTimestamp() to return correct
millis-since GMT when .getTime() is called on
the return value (currently default is false
for legacy behavior).
(Bug #14562)
Extraneous sleep on autoReconnect.
(Bug #13775)
Reconnect during middle of executeBatch()
should not occur if autoReconnect is enabled.
(Bug #13255)
maxQuerySizeToLog is not respected. Added
logging of bound values for execute() phase
of server-side prepared statements when
profileSQL=true as well.
(Bug #13048)
OpenOffice expects
DBMD.supportsIntegrityEnhancementFacility()
to return true if foreign keys are supported
by the datasource, even though this method also covers support
for check constraints, which MySQL doesn't
have. Setting the configuration property
overrideSupportsIntegrityEnhancementFacility
to true causes the driver to return
true for this method.
(Bug #12975)
Added com.mysql.jdbc.testsuite.url.default
system property to set default JDBC url for testsuite (to speed
up bug resolution when I'm working in Eclipse).
(Bug #12975)
logSlowQueries should give better info.
(Bug #12230)
Don't increase timeout for failover/reconnect. (Bug #6577)
Fixed client-side prepared statement bug with embedded
? characters inside quoted identifiers (it
was recognized as a placeholder, when it was not).
Do not permit executeBatch() for
CallableStatements with registered
OUT/INOUT parameters (JDBC
compliance).
Fall back to platform-encoding for
URLDecoder.decode() when parsing driver URL
properties if the platform doesn't have a two-argument version
of this method.
Bugs Fixed
The configuration property sessionVariables
now permits you to specify variables that start with the
“@” sign.
(Bug #13453)
URL configuration parameters do not permit
“&” or
“=” in their values. The JDBC
driver now parses configuration parameters as if they are
encoded using the application/x-www-form-urlencoded format as
specified by java.net.URLDecoder
(http://java.sun.com/j2se/1.5.0/docs/api/java/net/URLDecoder.html).
If the “%” character is present
in a configuration property, it must now be represented as
%25, which is the encoded form of
“%” when using
application/x-www-form-urlencoded encoding.
(Bug #13453)
Workaround for Bug #13374:
ResultSet.getStatement() on closed result set
returns NULL (as per JDBC 4.0 spec, but not
backward-compatible). Set the connection property
retainStatementAfterResultSetClose to
true to be able to retrieve a
ResultSet's statement after the
ResultSet has been closed using
.getStatement() (the default is
false, to be JDBC-compliant and to reduce the
chance that code using JDBC leaks Statement
instances).
(Bug #13277)
ResultSetMetaData from
Statement.getGeneratedKeys() caused a
NullPointerException to be thrown whenever a
method that required a connection reference was called.
(Bug #13277)
Backport of VAR[BINARY|CHAR] [BINARY] types
detection from 5.0 branch.
(Bug #13277)
Fixed NullPointerException when converting
catalog parameter in many
DatabaseMetaDataMethods to
byte[]s (for the result set) when the
parameter is null. (null
is not technically permitted by the JDBC specification, but we
have historically permitted it).
(Bug #13277)
Backport of Field class,
ResultSetMetaData.getColumnClassName(), and
ResultSet.getObject(int) changes from 5.0
branch to fix behavior surrounding VARCHAR
BINARY/VARBINARY and
related types.
(Bug #13277)
Read response in MysqlIO.sendFileToServer(),
even if the local file can't be opened, otherwise next query
issued will fail, because it is reading the response to the
empty LOAD DATA
INFILE packet sent to the server.
(Bug #13277)
When gatherPerfMetrics is enabled for servers
older than 4.1.0, a NullPointerException is
thrown from the constructor of ResultSet if
the query doesn't use any tables.
(Bug #13043)
java.sql.Types.OTHER returned for
BINARY and
VARBINARY columns when using
DatabaseMetaData.getColumns().
(Bug #12970)
ServerPreparedStatement.getBinding() now
checks if the statement is closed before attempting to reference
the list of parameter bindings, to avoid throwing a
NullPointerException.
(Bug #12970)
Tokenizer for = in URL properties was causing
sessionVariables=.... to be parameterized
incorrectly.
(Bug #12753)
cp1251 incorrectly mapped to
win1251 for servers newer than 4.0.x.
(Bug #12752)
getExportedKeys()
(Bug #12541)
Specifying a catalog works as stated in the API docs. (Bug #12541)
Specifying NULL means that catalog will not
be used to filter the results (thus all databases will be
searched), unless you've set
nullCatalogMeansCurrent=true in your JDBC URL
properties.
(Bug #12541)
getIndexInfo()
(Bug #12541)
getProcedures() (and thus indirectly
getProcedureColumns())
(Bug #12541)
getImportedKeys()
(Bug #12541)
Specifying "" means “current”
catalog, even though this isn't quite JDBC spec compliant, it is
there for legacy users.
(Bug #12541)
getCrossReference()
(Bug #12541)
Added Connection.isMasterConnection() for
clients to be able to determine if a multi-host master/slave
connection is connected to the first host in the list.
(Bug #12541)
getColumns()
(Bug #12541)
Handling of catalog argument in
DatabaseMetaData.getIndexInfo(), which also
means changes to the following methods in
DatabaseMetaData:
getBestRowIdentifier()
getColumns()
getCrossReference()
getExportedKeys()
getImportedKeys()
getIndexInfo()
getPrimaryKeys()
getProcedures() (and thus indirectly
getProcedureColumns())
getTables()
The catalog argument in all of these methods
now behaves in the following way:
Specifying NULL means that catalog will
not be used to filter the results (thus all databases will
be searched), unless you've set
nullCatalogMeansCurrent=true in your JDBC
URL properties.
Specifying "" means
“current” catalog, even though this isn't quite
JDBC spec compliant, it is there for legacy users.
Specifying a catalog works as stated in the API docs.
Made Connection.clientPrepare() available
from “wrapped” connections in the
jdbc2.optional package (connections built
by ConnectionPoolDataSource instances).
(Bug #12541)
getBestRowIdentifier()
(Bug #12541)
Made Connection.clientPrepare() available
from “wrapped” connections in the
jdbc2.optional package (connections built by
ConnectionPoolDataSource instances).
(Bug #12541)
getTables()
(Bug #12541)
getPrimaryKeys()
(Bug #12541)
Connection.prepareCall() is database name
case-sensitive (on Windows systems).
(Bug #12417)
explainSlowQueries hangs with server-side
prepared statements.
(Bug #12229)
Properties shared between master and slave with replication connection. (Bug #12218)
Geometry types not handled with server-side prepared statements. (Bug #12104)
maxPerformance.properties mis-spells
“elideSetAutoCommits”.
(Bug #11976)
ReplicationConnection won't switch to slave,
throws “Catalog can't be null” exception.
(Bug #11879)
Pstmt.setObject(...., Types.BOOLEAN) throws
exception.
(Bug #11798)
Escape tokenizer doesn't respect stacked single quotation marks for escapes. (Bug #11797)
GEOMETRY type not recognized when using
server-side prepared statements.
(Bug #11797)
Foreign key information that is quoted is parsed incorrectly
when DatabaseMetaData methods use that
information.
(Bug #11781)
The sendBlobChunkSize property is now clamped
to max_allowed_packet with
consideration of stream buffer size and packet headers to avoid
PacketTooBigExceptions when
max_allowed_packet is similar
in size to the default sendBlobChunkSize
which is 1M.
(Bug #11781)
CallableStatement.clearParameters() now
clears resources associated with
INOUT/OUTPUT parameters as
well as INPUT parameters.
(Bug #11781)
Fixed regression caused by fix for Bug #11552 that caused driver to return incorrect values for unsigned integers when those integers where within the range of the positive signed type. (Bug #11663)
Moved source code to Subversion repository. (Bug #11663)
Incorrect generation of testcase scripts for server-side prepared statements. (Bug #11663)
Fixed statements generated for testcases missing
; for “plain” statements.
(Bug #11629)
Spurious ! on console when character encoding
is utf8.
(Bug #11629)
StringUtils.getBytes() doesn't work when
using multi-byte character encodings and a length in
characters is specified.
(Bug #11614)
DBMD.storesLower/Mixed/UpperIdentifiers()
reports incorrect values for servers deployed on Windows.
(Bug #11575)
Reworked Field class,
*Buffer, and MysqlIO to be
aware of field lengths >
Integer.MAX_VALUE.
(Bug #11498)
Escape processor didn't honor strings demarcated with double quotation marks. (Bug #11498)
Updated DBMD.supportsCorrelatedQueries() to
return true for versions > 4.1,
supportsGroupByUnrelated() to return
true and
getResultSetHoldability() to return
HOLD_CURSORS_OVER_COMMIT.
(Bug #11498)
Lifted restriction of changing streaming parameters with
server-side prepared statements. As long as
all streaming parameters were set before
execution, .clearParameters() does not have
to be called. (due to limitation of client/server protocol,
prepared statements can not reset
individual stream data on the server side).
(Bug #11498)
ResultSet.moveToCurrentRow() fails to work
when preceded by a call to
ResultSet.moveToInsertRow().
(Bug #11190)
VARBINARY data corrupted when
using server-side prepared statements and
.setBytes().
(Bug #11115)
Statement.getWarnings() fails with NPE if
statement has been closed.
(Bug #10630)
Only get char[] from SQL in
PreparedStatement.ParseInfo() when needed.
(Bug #10630)
Bugs Fixed
Initial implemention of ParameterMetadata for
PreparedStatement.getParameterMetadata().
Only works fully for CallableStatements, as
current server-side prepared statements return every parameter
as a VARCHAR type.
Fixed connecting without a database specified raised an
exception in MysqlIO.changeDatabaseTo().
Bugs Fixed
Production package doesn't include JBoss integration classes. (Bug #11411)
Removed nonsensical “costly type conversion” warnings when using usage advisor. (Bug #11411)
Fixed PreparedStatement.setClob() not
accepting null as a parameter.
(Bug #11360)
Connector/J dumping query into SQLException
twice.
(Bug #11360)
autoReconnect ping causes exception on
connection startup.
(Bug #11259)
Connection.setCatalog() is now aware of the
useLocalSessionState configuration property,
which when set to true will prevent the
driver from sending USE ... to the server if
the requested catalog is the same as the current catalog.
(Bug #11115)
3-0-Compat: Compatibility with Connector/J
3.0.x functionality
(Bug #11115)
maxPerformance: Maximum performance without
being reckless
(Bug #11115)
solarisMaxPerformance: Maximum performance
for Solaris, avoids syscalls where it can
(Bug #11115)
Added maintainTimeStats configuration
property (defaults to true), which tells the
driver whether or not to keep track of the last query time and
the last successful packet sent to the server's time. If set to
false, removes two syscalls per query.
(Bug #11115)
VARBINARY data corrupted when
using server-side prepared statements and
ResultSet.getBytes().
(Bug #11115)
Added the following configuration bundles, use one or many using
the useConfigs configuration property:
maxPerformance: Maximum performance
without being reckless
solarisMaxPerformance: Maximum
performance for Solaris, avoids syscalls where it can
3-0-Compat: Compatibility with
Connector/J 3.0.x functionality
(Bug #11115)
Try to handle OutOfMemoryErrors more
gracefully. Although not much can be done, they will in most
cases close the connection they happened on so that further
operations don't run into a connection in some unknown state.
When an OOM has happened, any further operations on the
connection will fail with a “Connection closed”
exception that will also list the OOM exception as the reason
for the implicit connection close event.
(Bug #10850)
Setting cachePrepStmts=true now causes the
Connection to also cache the check the driver
performs to determine if a prepared statement can be server-side
or not, as well as caches server-side prepared statements for
the lifetime of a connection. As before, the
prepStmtCacheSize parameter controls the size
of these caches.
(Bug #10850)
Don't send COM_RESET_STMT for each execution
of a server-side prepared statement if it isn't required.
(Bug #10850)
0-length streams not sent to server when using server-side prepared statements. (Bug #10850)
Driver detects if you're running MySQL-5.0.7 or later, and does
not scan for LIMIT ?[,?] in statements being
prepared, as the server supports those types of queries now.
(Bug #10850)
Reorganized directory layout. Sources now are in
src folder. Don't pollute parent directory
when building, now output goes to ./build,
distribution goes to ./dist.
(Bug #10496)
Added support/bug hunting feature that generates
.sql test scripts to
STDERR when
autoGenerateTestcaseScript is set to
true.
(Bug #10496)
SQLException is thrown when using property
characterSetResults with
cp932 or eucjpms.
(Bug #10496)
The data type returned for TINYINT(1) columns
when tinyInt1isBit=true (the default) can be
switched between Types.BOOLEAN and
Types.BIT using the new configuration
property transformedBitIsBoolean, which
defaults to false. If set to
false (the default),
DatabaseMetaData.getColumns() and
ResultSetMetaData.getColumnType() will return
Types.BOOLEAN for
TINYINT(1) columns. If
true, Types.BOOLEAN will
be returned instead. Regardless of this configuration property,
if tinyInt1isBit is enabled, columns with the
type TINYINT(1) will be returned as
java.lang.Boolean instances from
ResultSet.getObject(...), and
ResultSetMetaData.getColumnClassName() will
return java.lang.Boolean.
(Bug #10485)
SQLException thrown when retrieving
YEAR(2) with
ResultSet.getString(). The driver will now
always treat YEAR types as
java.sql.Dates and return the correct values
for getString(). Alternatively, the
yearIsDateType connection property can be set
to false and the values will be treated as
SHORTs.
(Bug #10485)
Driver doesn't support {?=CALL(...)} for
calling stored functions. This involved adding support for
function retrieval to
DatabaseMetaData.getProcedures() and
getProcedureColumns() as well.
(Bug #10310)
Unsigned SMALLINT treated as
signed for ResultSet.getInt(), fixed all
cases for UNSIGNED integer values and
server-side prepared statements, as well as
ResultSet.getObject() for UNSIGNED
TINYINT.
(Bug #10156)
Made ServerPreparedStatement.asSql() work
correctly so auto-explain functionality would work with
server-side prepared statements.
(Bug #10155)
Double quotation marks not recognized when parsing client-side prepared statements. (Bug #10155)
Made JDBC2-compliant wrappers public to enable access to vendor extensions. (Bug #10155)
DatabaseMetaData.supportsMultipleOpenResults()
now returns true. The driver has supported
this for some time, DBMD just missed that fact.
(Bug #10155)
Cleaned up logging of profiler events, moved code to dump a
profiler event as a string to
com.mysql.jdbc.log.LogUtils so that third
parties can use it.
(Bug #10155)
Made enableStreamingResults() visible on
com.mysql.jdbc.jdbc2.optional.StatementWrapper.
(Bug #10155)
Actually write manifest file to correct place so it ends up in the binary jar file. (Bug #10144)
Added createDatabaseIfNotExist property
(default is false), which will cause the
driver to ask the server to create the database specified in the
URL if it doesn't exist. You must have the appropriate
privileges for database creation for this to work.
(Bug #10144)
Memory leak in ServerPreparedStatement if
serverPrepare() fails.
(Bug #10144)
com.mysql.jdbc.PreparedStatement.ParseInfo
does unnecessary call to toCharArray().
(Bug #9064)
Driver now correctly uses CP932 if available on the server for Windows-31J, CP932 and MS932 java encoding names, otherwise it resorts to SJIS, which is only a close approximation. Currently only MySQL-5.0.3 and newer (and MySQL-4.1.12 or .13, depending on when the character set gets backported) can reliably support any variant of CP932.
Overhaul of character set configuration, everything now lives in a properties file.
Bugs Fixed
Should accept null for catalog (meaning use
current) in DBMD methods, even though it is not JDBC-compliant
for legacy's sake. Disable by setting connection property
nullCatalogMeansCurrent to
false (which will be the default value in C/J
3.2.x).
(Bug #9917)
Fixed driver not returning true for
-1 when
ResultSet.getBoolean() was called on result
sets returned from server-side prepared statements.
(Bug #9778)
Added a Manifest.MF file with
implementation information to the .jar
file.
(Bug #9778)
More tests in Field.isOpaqueBinary() to
distinguish opaque binary (that is, fields with type
CHAR(n) and CHARACTER SET
BINARY) from output of various scalar and aggregate
functions that return strings.
(Bug #9778)
DBMD.getTables() shouldn't return tables if
views are asked for, even if the database version doesn't
support views.
(Bug #9778)
Should accept null for name patterns in DBMD
(meaning “%”), even though it
isn't JDBC compliant, for legacy's sake. Disable by setting
connection property nullNamePatternMatchesAll
to false (which will be the default value in
C/J 3.2.x).
(Bug #9769)
The performance metrics feature now gathers information about number of tables referenced in a SELECT. (Bug #9704)
The logging system is now automatically configured. If the value
has been set by the user, using the URL property
logger or the system property
com.mysql.jdbc.logger, then use that,
otherwise, autodetect it using the following steps:
Log4j, if it is available,
Then JDK1.4 logging,
Then fallback to our STDERR logging.
(Bug #9704)
Statement.getMoreResults() could throw NPE
when existing result set was .close()d.
(Bug #9704)
Stored procedures with DECIMAL
parameters with storage specifications that contained
“,” in them would fail.
(Bug #9682)
PreparedStatement.setObject(int, Object, int type, int
scale) now uses scale value for
BigDecimal instances.
(Bug #9682)
Added support for the c3p0 connection pool's
(http://c3p0.sf.net/) validation/connection
checker interface which uses the lightweight
COM_PING call to the server if available. To
use it, configure your c3p0 connection pool's
connectionTesterClassName property to use
com.mysql.jdbc.integration.c3p0.MysqlConnectionTester.
(Bug #9320)
PreparedStatement.getMetaData() inserts blank
row in database under certain conditions when not using
server-side prepared statements.
(Bug #9320)
Better detection of LIMIT inside/outside of
quoted strings so that the driver can more correctly determine
whether a prepared statement can be prepared on the server or
not.
(Bug #9320)
Connection.canHandleAsPreparedStatement() now
makes “best effort” to distinguish
LIMIT clauses with placeholders in them from
ones without to have fewer false positives when generating
work-arounds for statements the server cannot currently handle
as server-side prepared statements.
(Bug #9320)
Fixed build.xml to not compile
log4j logging if log4j not
available.
(Bug #9320)
Added finalizers to ResultSet and
Statement implementations to be JDBC
spec-compliant, which requires that if not explicitly closed,
these resources should be closed upon garbage collection.
(Bug #9319)
Stored procedures with same name in different databases confuse the driver when it tries to determine parameter counts/types. (Bug #9319)
A continuation of Bug #8868, where functions used in queries
that should return nonstring types when resolved by temporary
tables suddenly become opaque binary strings (work-around for
server limitation). Also fixed fields with type of
CHAR(n) CHARACTER SET BINARY to return
correct/matching classes for
RSMD.getColumnClassName() and
ResultSet.getObject().
(Bug #9236)
Cannot use UTF-8 for characterSetResults
configuration property.
(Bug #9206)
PreparedStatement.addBatch() doesn't work
with server-side prepared statements and streaming
BINARY data.
(Bug #9040)
ServerPreparedStatements now correctly
“stream”
BLOB/CLOB data
to the server. You can configure the threshold chunk size using
the JDBC URL property blobSendChunkSize (the
default is 1MB).
(Bug #8868)
DATE_FORMAT() queries returned as
BLOBs from
getObject().
(Bug #8868)
Server-side session variables can be preset at connection time
by passing them as a comma-delimited list for the connection
property sessionVariables.
(Bug #8868)
BlobFromLocator now uses correct identifier
quoting when generating prepared statements.
(Bug #8868)
Fixed regression in ping() for users using
autoReconnect=true.
(Bug #8868)
Check for empty strings ('') when converting
CHAR/VARCHAR
column data to numbers, throw exception if
emptyStringsConvertToZero configuration
property is set to false (for
backward-compatibility with 3.0, it is now set to
true by default, but will most likely default
to false in 3.2).
(Bug #8803)
DATA_TYPE column from
DBMD.getBestRowIdentifier() causes
ArrayIndexOutOfBoundsException when accessed
(and in fact, didn't return any value).
(Bug #8803)
DBMD.supportsMixedCase*Identifiers() returns
wrong value on servers running on case-sensitive file systems.
(Bug #8800)
DBMD.supportsResultSetConcurrency() not
returning true for forward-only/read-only
result sets (we obviously support this).
(Bug #8792)
Fixed ResultSet.getTime() on a
NULL value for server-side prepared
statements throws NPE.
Made Connection.ping() a public method.
Added support for new precision-math
DECIMAL type in MySQL 5.0.3 and
up.
Fixed DatabaseMetaData.getTables() returning
views when they were not asked for as one of the requested table
types.
Bugs Fixed
PreparedStatements not creating streaming
result sets.
(Bug #8487)
Don't pass NULL to
String.valueOf() in
ResultSet.getNativeConvertToString(), as it
stringifies it (that is, returns null), which
is not correct for the method in question.
(Bug #8487)
Fixed NPE in ResultSet.realClose() when using
usage advisor and result set was already closed.
(Bug #8428)
ResultSet.getString() doesn't maintain format
stored on server, bug fix only enabled when
noDatetimeStringSync property is set to
true (the default is
false).
(Bug #8428)
Added support for BIT type in
MySQL-5.0.3. The driver will treat BIT(1-8)
as the JDBC standard BIT type
(which maps to java.lang.Boolean), as the
server does not currently send enough information to determine
the size of a bitfield when < 9 bits are declared.
BIT(>9) will be treated as
VARBINARY, and will return
byte[] when getObject() is
called.
(Bug #8424)
Added useLocalSessionState configuration
property, when set to true the JDBC driver
trusts that the application is well-behaved and only sets
autocommit and transaction isolation levels using the methods
provided on java.sql.Connection, and
therefore can manipulate these values in many cases without
incurring round-trips to the database server.
(Bug #8424)
Added enableStreamingResults() to
Statement for connection pool implementations
that check Statement.setFetchSize() for
specification-compliant values. Call
Statement.setFetchSize(>=0) to disable the
streaming results for that statement.
(Bug #8424)
ResultSet.getBigDecimal() throws exception
when rounding would need to occur to set scale. The driver now
chooses a rounding mode of “half up” if nonrounding
BigDecimal.setScale() fails.
(Bug #8424)
Fixed synchronization issue with
ServerPreparedStatement.serverPrepare() that
could cause deadlocks/crashes if connection was shared between
threads.
(Bug #8096)
Emulated locators corrupt binary data when using server-side prepared statements. (Bug #8096)
Infinite recursion when “falling back” to master in failover configuration. (Bug #7952)
Disable multi-statements (if enabled) for MySQL-4.1 versions prior to version 4.1.10 if the query cache is enabled, as the server returns wrong results in this configuration. (Bug #7952)
Removed dontUnpackBinaryResults
functionality, the driver now always stores results from
server-side prepared statements as is from the server and
unpacks them on demand.
(Bug #7952)
Fixed duplicated code in
configureClientCharset() that prevented
useOldUTF8Behavior=true from working
properly.
(Bug #7952)
Added holdResultsOpenOverStatementClose
property (default is false), that keeps
result sets open over statement.close() or new execution on same
statement (suggested by Kevin Burton).
(Bug #7715)
Detect new sql_mode variable in
string form (it used to be integer) and adjust quoting method
for strings appropriately.
(Bug #7715)
Timestamps converted incorrectly to strings with server-side prepared statements and updatable result sets. (Bug #7715)
Timestamp key column data needed _binary
stripped for UpdatableResultSet.refreshRow().
(Bug #7686)
Choose correct “direction” to apply time
adjustments when both client and server are in GMT time zone
when using ResultSet.get(..., cal) and
PreparedStatement.set(...., cal).
(Bug #4718)
Remove _binary introducer from parameters
used as in/out parameters in
CallableStatement.
(Bug #4718)
Always return byte[]s for output parameters
registered as *BINARY.
(Bug #4718)
By default, the driver now scans SQL you are preparing using all
variants of Connection.prepareStatement() to
determine if it is a supported type of statement to prepare on
the server side, and if it is not supported by the server, it
instead prepares it as a client-side emulated prepared
statement. You can disable this by passing
emulateUnsupportedPstmts=false in your JDBC
URL.
(Bug #4718)
Added dontTrackOpenResources option (default
is false, to be JDBC compliant), which helps
with memory use for nonwell-behaved apps (that is, applications
that don't close Statement objects when they
should).
(Bug #4718)
Send correct value for “boolean”
true to server for
PreparedStatement.setObject(n, "true",
Types.BIT).
(Bug #4718)
Fixed bug with Connection not caching statements from
prepareStatement() when the statement wasn't
a server-side prepared statement.
(Bug #4718)
Bugs Fixed
DBMD.getProcedures() doesn't respect catalog
parameter.
(Bug #7026)
Fixed hang on SocketInputStream.read() with
Statement.setMaxRows() and multiple result
sets when driver has to truncate result set directly, rather
than tacking a LIMIT
on the end of it.
n
Bugs Fixed
Use 1MB packet for sending file for
LOAD DATA LOCAL
INFILE if that is <
max_allowed_packet on server.
(Bug #6537)
SUM() on
DECIMAL with server-side prepared
statement ignores scale if zero-padding is needed (this ends up
being due to conversion to DOUBLE
by server, which when converted to a string to parse into
BigDecimal, loses all “padding”
zeros).
(Bug #6537)
Use
DatabaseMetaData.getIdentifierQuoteString()
when building DBMD queries.
(Bug #6537)
Use our own implementation of buffered input streams to get
around blocking behavior of
java.io.BufferedInputStream. Disable this
with useReadAheadInput=false.
(Bug #6399)
Make auto-deserialization of
java.lang.Objects stored in
BLOB columns configurable using
autoDeserialize property (defaults to
false).
(Bug #6399)
ResultSetMetaData.getColumnDisplaySize()
returns incorrect values for multi-byte charsets.
(Bug #6399)
Re-work Field.isOpaqueBinary() to detect
CHAR( to support fixed-length binary fields for
n) CHARACTER SET
BINARYResultSet.getObject().
(Bug #6399)
Failing to connect to the server when one of the addresses for
the given host name is IPV6 (which the server does not yet bind
on). The driver now loops through all IP
addresses for a given host, and stops on the first one that
accepts() a
socket.connect().
(Bug #6348)
Removed unwanted new Throwable() in
ResultSet constructor due to bad merge
(caused a new object instance that was never used for every
result set created). Found while profiling for Bug #6359.
(Bug #6225)
ServerSidePreparedStatement allocating
short-lived objects unnecessarily.
(Bug #6225)
Use null-safe-equals for key comparisons in updatable result sets. (Bug #6225)
Fixed too-early creation of StringBuffer in
EscapeProcessor.escapeSQL(), also return
String when escaping not needed (to avoid
unnecessary object allocations). Found while profiling for Bug
#6359.
(Bug #6225)
UNSIGNED BIGINT unpacked incorrectly from
server-side prepared statement result sets.
(Bug #5729)
Added experimental configuration property
dontUnpackBinaryResults, which delays
unpacking binary result set values until they're asked for, and
only creates object instances for nonnumeric values (it is set
to false by default). For some usecase/jvm
combinations, this is friendlier on the garbage collector.
(Bug #5706)
Don't throw exceptions for
Connection.releaseSavepoint().
(Bug #5706)
Inefficient detection of pre-existing string instances in
ResultSet.getNativeString().
(Bug #5706)
Use a per-session Calendar instance by
default when decoding dates from
ServerPreparedStatements (set to old, less
performant behavior by setting property
dynamicCalendars=true).
(Bug #5706)
Fixed batched updates with server prepared statements weren't looking if the types had changed for a given batched set of parameters compared to the previous set, causing the server to return the error “Wrong arguments to mysql_stmt_execute()”. (Bug #5235)
Handle case when string representation of timestamp contains
trailing “.” with no numbers
following it.
(Bug #5235)
Server-side prepared statements did not honor
zeroDateTimeBehavior property, and would
cause class-cast exceptions when using
ResultSet.getObject(), as the all-zero string
was always returned.
(Bug #5235)
Fix comparisons made between string constants and dynamic
strings that are converted with either
toUpperCase() or
toLowerCase() to use
Locale.ENGLISH, as some locales
“override” case rules for English. Also use
StringUtils.indexOfIgnoreCase() instead of
.toUpperCase().indexOf(), avoids creating a
very short-lived transient String instance.
Bugs Fixed
Fixed ServerPreparedStatement to read
prepared statement metadata off the wire, even though it is
currently a placeholder instead of using
MysqlIO.clearInputStream() which didn't work
at various times because data wasn't available to read from the
server yet. This fixes sporadic errors users were having with
ServerPreparedStatements throwing
ArrayIndexOutOfBoundExceptions.
(Bug #5032)
Added three ways to deal with all-zero datetimes when reading
them from a ResultSet:
exception (the default), which throws an
SQLException with an SQLState of
S1009; convertToNull,
which returns NULL instead of the date; and
round, which rounds the date to the nearest
closest value which is '0001-01-01'.
(Bug #5032)
The driver is more strict about truncation of numerics on
ResultSet.get*(), and will throw an
SQLException when truncation is detected. You
can disable this by setting
jdbcCompliantTruncation to
false (it is enabled by default, as this
functionality is required for JDBC compliance).
(Bug #5032)
You can now use URLs in
LOAD DATA LOCAL
INFILE statements, and the driver will use Java's
built-in handlers for retrieving the data and sending it to the
server. This feature is not enabled by default, you must set the
allowUrlInLocalInfile connection property to
true.
(Bug #5032)
ResultSet.getObject() doesn't return type
Boolean for pseudo-bit types from prepared
statements on 4.1.x (shortcut for avoiding extra type conversion
when using binary-encoded result sets obscured test in
getObject() for “pseudo” bit
type).
(Bug #5032)
Use com.mysql.jdbc.Message's classloader when
loading resource bundle, should fix sporadic issues when the
caller's classloader can't locate the resource bundle.
(Bug #5032)
ServerPreparedStatements dealing with return
of DECIMAL type don't work.
(Bug #5012)
Track packet sequence numbers if
enablePacketDebug=true, and throw an
exception if packets received out-of-order.
(Bug #4689)
ResultSet.wasNull() does not work for
primitives if a previous null was returned.
(Bug #4689)
Optimized integer number parsing, enable “old”
slower integer parsing using JDK classes using
useFastIntParsing=false property.
(Bug #4642)
Added useOnlyServerErrorMessages property,
which causes message text in exceptions generated by the server
to only contain the text sent by the server (as opposed to the
SQLState's “standard” description, followed by the
server's error message). This property is set to
true by default.
(Bug #4642)
ServerPreparedStatement.execute*() sometimes
threw ArrayIndexOutOfBoundsException when
unpacking field metadata.
(Bug #4642)
Connector/J 3.1.3 beta does not handle integers correctly
(caused by changes to support unsigned reads in
Buffer.readInt() ->
Buffer.readShort()).
(Bug #4510)
Added support in DatabaseMetaData.getTables()
and getTableTypes() for views, which are now
available in MySQL server 5.0.x.
(Bug #4510)
ResultSet.getObject() returns wrong type for
strings when using prepared statements.
(Bug #4482)
Calling MysqlPooledConnection.close() twice
(even though an application error), caused NPE. Fixed.
(Bug #4482)
Bugs Fixed
Support new time zone variables in MySQL-4.1.3 when
useTimezone=true.
(Bug #4311)
Error in retrieval of mediumint column with
prepared statements and binary protocol.
(Bug #4311)
Support for unsigned numerics as return types from prepared
statements. This also causes a change in
ResultSet.getObject() for the bigint
unsigned type, which used to return
BigDecimal instances, it now returns
instances of java.lang.BigInteger.
(Bug #4311)
Externalized more messages (on-going effort). (Bug #4119)
Null bitmask sent for server-side prepared statements was incorrect. (Bug #4119)
Added constants for MySQL error numbers (publicly accessible,
see com.mysql.jdbc.MysqlErrorNumbers), and
the ability to generate the mappings of vendor error codes to
SQLStates that the driver uses (for documentation purposes).
(Bug #4119)
Added packet debugging code (see the
enablePacketDebug property documentation).
(Bug #4119)
Use SQL Standard SQL states by default, unless
useSqlStateCodes property is set to
false.
(Bug #4119)
Mangle output parameter names for
CallableStatements so they will not clash
with user variable names.
Added support for INOUT parameters in
CallableStatements.
Bugs Fixed
Don't enable server-side prepared statements for server version 5.0.0 or 5.0.1, as they aren't compatible with the '4.1.2+' style that the driver uses (the driver expects information to come back that isn't there, so it hangs). (Bug #3804)
getWarnings() returns
SQLWarning instead of
DataTruncation.
(Bug #3804)
getProcedureColumns() doesn't work with
wildcards for procedure name.
(Bug #3540)
getProcedures() does not return any
procedures in result set.
(Bug #3539)
Fixed DatabaseMetaData.getProcedures() when
run on MySQL-5.0.0 (output of SHOW
PROCEDURE STATUS changed between 5.0.0 and 5.0.1.
(Bug #3520)
Added connectionCollation property to cause
driver to issue set collation_connection=...
query on connection init if default collation for given charset
is not appropriate.
(Bug #3520)
DBMD.getSQLStateType() returns incorrect
value.
(Bug #3520)
Correctly map output parameters to position given in
prepareCall() versus. order implied during
registerOutParameter().
(Bug #3146)
Cleaned up detection of server properties. (Bug #3146)
Correctly detect initial character set for servers >= 4.1.0. (Bug #3146)
Support placeholder for parameter metadata for server >= 4.1.2. (Bug #3146)
Added gatherPerformanceMetrics property,
along with properties to control when/where this info gets
logged (see docs for more info).
Fixed case when no parameters could cause a
NullPointerException in
CallableStatement.setOutputParameters().
Enabled callable statement caching using
cacheCallableStmts property.
Fixed sending of split packets for large queries, enabled nio ability to send large packets as well.
Added .toString() functionality to
ServerPreparedStatement, which should help if
you're trying to debug a query that is a prepared statement (it
shows SQL as the server would process).
Added logSlowQueries property, along with
slowQueriesThresholdMillis property to
control when a query should be considered “slow.”
Removed wrapping of exceptions in
MysqlIO.changeUser().
Fixed stored procedure parameter parsing info when size was
specified for a parameter (for example,
char(), varchar()).
ServerPreparedStatements weren't actually
de-allocating server-side resources when
.close() was called.
Fixed case when no output parameters specified for a stored procedure caused a bogus query to be issued to retrieve out parameters, leading to a syntax error from the server.
Bugs Fixed
Use DocBook version of docs for shipped versions of drivers. (Bug #2671)
NULL fields were not being encoded correctly
in all cases in server-side prepared statements.
(Bug #2671)
Fixed rare buffer underflow when writing numbers into buffers for sending prepared statement execution requests. (Bug #2671)
Fixed ConnectionProperties that weren't
properly exposed through accessors, cleaned up
ConnectionProperties code.
(Bug #2623)
Class-cast exception when using scrolling result sets and server-side prepared statements. (Bug #2623)
Merged unbuffered input code from 3.0. (Bug #2623)
Enabled streaming of result sets from server-side prepared statements. (Bug #2606)
Server-side prepared statements were not returning data type
YEAR correctly.
(Bug #2606)
Fixed charset conversion issue in
getTables().
(Bug #2502)
Implemented multiple result sets returned from a statement or stored procedure. (Bug #2502)
Implemented Connection.prepareCall(), and
DatabaseMetaData.
getProcedures() and
getProcedureColumns().
(Bug #2359)
Merged prepared statement caching, and
.getMetaData() support from 3.0 branch.
(Bug #2359)
Fixed off-by-1900 error in some cases for years in
TimeUtil.fastDate/TimeCreate()
when unpacking results from server-side prepared statements.
(Bug #2359)
Reset long binary parameters in
ServerPreparedStatement when
clearParameters() is called, by sending
COM_RESET_STMT to the server.
(Bug #2359)
NULL values for numeric types in binary
encoded result sets causing
NullPointerExceptions.
(Bug #2359)
Display where/why a connection was implicitly closed (to aid debugging). (Bug #1673)
DatabaseMetaData.getColumns() is not
returning correct column ordinal info for
non-'%' column name patterns.
(Bug #1673)
Fixed NullPointerException in
ServerPreparedStatement.setTimestamp(), as
well as year and month discrepencies in
ServerPreparedStatement.setTimestamp(),
setDate().
(Bug #1673)
Added ability to have multiple database/JVM targets for
compliance and regression/unit tests in
build.xml.
(Bug #1673)
Fixed sending of queries larger than 16M. (Bug #1673)
Merged fix of data type mapping from MySQL type
FLOAT to
java.sql.Types.REAL from 3.0 branch.
(Bug #1673)
Fixed NPE and year/month bad conversions when accessing some
datetime functionality in
ServerPreparedStatements and their resultant
result sets.
(Bug #1673)
Added named and indexed input/output parameter support to
CallableStatement. MySQL-5.0.x or newer.
(Bug #1673)
CommunicationsException implemented, that
tries to determine why communications was lost with a server,
and displays possible reasons when
.getMessage() is called.
(Bug #1673)
Detect collation of column for
RSMD.isCaseSensitive().
(Bug #1673)
Optimized Buffer.readLenByteArray() to return
shared empty byte array when length is 0.
Fix support for table aliases when checking for all primary keys
in UpdatableResultSet.
Unpack “unknown” data types from server prepared
statements as Strings.
Implemented Statement.getWarnings() for
MySQL-4.1 and newer (using SHOW
WARNINGS).
Ensure that warnings are cleared before executing queries on prepared statements, as-per JDBC spec (now that we support warnings).
Correctly initialize datasource properties from JNDI Refs, including explicitly specified URLs.
Implemented long data (Blobs, Clobs, InputStreams, Readers) for server prepared statements.
Deal with 0-length tokens in EscapeProcessor
(caused by callable statement escape syntax).
DatabaseMetaData now reports
supportsStoredProcedures() for MySQL versions
>= 5.0.0
Support for mysql_change_user().
See the changeUser() method in
com.mysql.jdbc.Connection.
Removed useFastDates connection property.
Support for NIO. Use useNIO=true on platforms
that support NIO.
Check for closed connection on delete/update/insert row
operations in UpdatableResultSet.
Support for transaction savepoints (MySQL >= 4.0.14 or 4.1.1).
Support “old” profileSql
capitalization in ConnectionProperties. This
property is deprecated, you should use
profileSQL if possible.
Fixed character encoding issues when converting bytes to ASCII when MySQL doesn't provide the character set, and the JVM is set to a multi-byte encoding (usually affecting retrieval of numeric values).
Centralized setting of result set type and concurrency.
Fixed bug with UpdatableResultSets not using
client-side prepared statements.
Default result set type changed to
TYPE_FORWARD_ONLY (JDBC compliance).
Fixed IllegalAccessError to
Calendar.getTimeInMillis() in
DateTimeValue (for JDK < 1.4).
Allow contents of PreparedStatement.setBlob()
to be retained between calls to .execute*().
Fixed stack overflow in
Connection.prepareCall() (bad merge).
Refactored how connection properties are set and exposed as
DriverPropertyInfo as well as
Connection and DataSource
properties.
Reduced number of methods called in average query to be more efficient.
Prepared Statements will be re-prepared on
auto-reconnect. Any errors encountered are postponed until first
attempt to re-execute the re-prepared statement.
Bugs Fixed
Added useServerPrepStmts property (default
false). The driver will use server-side
prepared statements when the server version supports them (4.1
and newer) when this property is set to true.
It is currently set to false by default until
all bind/fetch functionality has been implemented. Currently
only DML prepared statements are implemented for 4.1 server-side
prepared statements.
Added requireSSL property.
Track open Statements, close all when
Connection.close() is called (JDBC
compliance).
Bugs Fixed
Workaround for server Bug #9098: Default values of
CURRENT_* for
DATE,
TIME,
DATETIME, and
TIMESTAMP columns can't be
distinguished from string values, so
UpdatableResultSet.moveToInsertRow()
generates bad SQL for inserting default values.
(Bug #8812)
NON_UNIQUE column from
DBMD.getIndexInfo() returned inverted value.
(Bug #8812)
EUCKR charset is sent as SET NAMES
euc_kr which MySQL-4.1 and newer doesn't understand.
(Bug #8629)
Added support for the EUC_JP_Solaris
character encoding, which maps to a MySQL encoding of
eucjpms (backported from 3.1 branch). This
only works on servers that support eucjpms,
namely 5.0.3 or later.
(Bug #8629)
Use hex escapes for
PreparedStatement.setBytes() for double-byte
charsets including “aliases”
Windows-31J, CP934,
MS932.
(Bug #8629)
DatabaseMetaData.supportsSelectForUpdate()
returns correct value based on server version.
(Bug #8629)
Which requires hex escaping of binary data when using multi-byte charsets with prepared statements. (Bug #8064)
Fixed duplicated code in
configureClientCharset() that prevented
useOldUTF8Behavior=true from working
properly.
(Bug #7952)
Backported SQLState codes mapping from Connector/J 3.1, enable
with useSqlStateCodes=true as a connection
property, it defaults to false in this
release, so that we don't break legacy applications (it defaults
to true starting with Connector/J 3.1).
(Bug #7686)
Timestamp key column data needed _binary
stripped for UpdatableResultSet.refreshRow().
(Bug #7686)
MS932, SHIFT_JIS, and
Windows_31J not recognized as aliases for
sjis.
(Bug #7607)
Handle streaming result sets with more than 2 billion rows properly by fixing wraparound of row number counter. (Bug #7601)
PreparedStatement.fixDecimalExponent() adding
extra +, making number unparseable by MySQL
server.
(Bug #7601)
Escape sequence {fn convert(..., type)} now supports ODBC-style
types that are prepended by SQL_.
(Bug #7601)
Statements created from a pooled connection were returning
physical connection instead of logical connection when
getConnection() was called.
(Bug #7316)
Support new protocol type MYSQL_TYPE_VARCHAR.
(Bug #7081)
Added useOldUTF8Behavior' configuration
property, which causes JDBC driver to act like it did with
MySQL-4.0.x and earlier when the character encoding is
utf-8 when connected to MySQL-4.1 or newer.
(Bug #7081)
DatabaseMetaData.getIndexInfo() ignored
unique parameter.
(Bug #7081)
PreparedStatement.fixDecimalExponent() adding
extra +, making number unparseable by MySQL
server.
(Bug #7061)
PreparedStatements don't encode Big5 (and
other multi-byte) character sets correctly in static SQL
strings.
(Bug #7033)
Connections starting up failed-over (due to down master) never retry master. (Bug #6966)
Adding CP943 to aliases for
sjis.
(Bug #6549, Bug #7607)
Timestamp/Time conversion
goes in the wrong “direction” when
useTimeZone=true and server time zone differs
from client time zone.
(Bug #5874)
Bugs Fixed
Made TINYINT(1) ->
BIT/Boolean
conversion configurable using tinyInt1isBit
property (default true to be JDBC compliant
out of the box).
(Bug #5664)
Off-by-one bug in
Buffer.readString(.
(Bug #5664)string)
ResultSet.updateByte() when on insert row
throws ArrayOutOfBoundsException.
(Bug #5664)
Fixed regression where useUnbufferedInput was
defaulting to false.
(Bug #5664)
ResultSet.getTimestamp() on a column with
TIME in it fails.
(Bug #5664)
Fixed DatabaseMetaData.getTypes() returning
incorrect (this is, nonnegative) scale for the
NUMERIC type.
(Bug #5664)
Only set character_set_results
during connection establishment if server version >= 4.1.1.
(Bug #5664)
Fixed ResultSetMetaData.isReadOnly() to
detect nonwritable columns when connected to MySQL-4.1 or newer,
based on existence of “original” table and column
names.
Re-issue character set configuration commands when re-using
pooled connections or Connection.changeUser()
when connected to MySQL-4.1 or newer.
Bugs Fixed
ResultSet.getMetaData() should not return
incorrectly initialized metadata if the result set has been
closed, but should instead throw an
SQLException. Also fixed for
getRow() and getWarnings()
and traversal methods by calling
checkClosed() before operating on
instance-level fields that are nullified during
.close().
(Bug #5069)
Use _binary introducer for
PreparedStatement.setBytes() and
set*Stream() when connected to MySQL-4.1.x or
newer to avoid misinterpretation during character conversion.
(Bug #5069)
Parse new time zone variables from 4.1.x servers. (Bug #5069)
ResultSet should release
Field[] instance in
.close().
(Bug #5022)
RSMD.getPrecision() returning 0 for
nonnumeric types (should return max length in chars for
nonbinary types, max length in bytes for binary types). This fix
also fixes mapping of RSMD.getColumnType()
and RSMD.getColumnTypeName() for the
BLOB types based on the length
sent from the server (the server doesn't distinguish between
TINYBLOB,
BLOB,
MEDIUMBLOB or
LONGBLOB at the network protocol
level).
(Bug #4880)
“Production” is now “GA” (General Availability) in naming scheme of distributions. (Bug #4860, Bug #4138)
DBMD.getColumns() returns incorrect JDBC type
for unsigned columns. This affects type mappings for all numeric
types in the RSMD.getColumnType() and
RSMD.getColumnTypeNames() methods as well, to
ensure that “like” types from
DBMD.getColumns() match up with what
RSMD.getColumnType() and
getColumnTypeNames() return.
(Bug #4860, Bug #4138)
Calling .close() twice on a
PooledConnection causes NPE.
(Bug #4808)
DOUBLE mapped twice in
DBMD.getTypeInfo().
(Bug #4742)
Added FLOSS license exemption. (Bug #4742)
Removed redundant calls to checkRowPos() in
ResultSet.
(Bug #4334)
Failover for autoReconnect not using port
numbers for any hosts, and not retrying all hosts.
This required a change to the SocketFactory
connect() method signature, which is now
public Socket connect(String host, int portNumber,
Properties props); therefore, any third-party socket
factories will have to be changed to support this signature.
(Bug #4334)
Logical connections created by
MysqlConnectionPoolDataSource will now issue
a rollback() when they are closed and sent
back to the pool. If your application server/connection pool
already does this for you, you can set the
rollbackOnPooledClose property to
false to avoid the overhead of an extra
rollback().
(Bug #4334)
StringUtils.escapeEasternUnicodeByteStream
was still broken for GBK.
(Bug #4010)
Bugs Fixed
No Database Selected when using
MysqlConnectionPoolDataSource.
(Bug #3920)
PreparedStatement.getGeneratedKeys() method
returns only 1 result for batched insertions.
(Bug #3873)
Using a MySQLDatasource without server name
fails.
(Bug #3848)
Bugs Fixed
Inconsistent reporting of data type. The server still doesn't return all types for *BLOBs *TEXT correctly, so the driver won't return those correctly. (Bug #3570)
UpdatableResultSet not picking up default
values for moveToInsertRow().
(Bug #3557)
Not specifying database in URL caused
MalformedURL exception.
(Bug #3554)
Auto-convert MySQL encoding names to Java encoding names if used
for characterEncoding property.
(Bug #3554)
Use junit.textui.TestRunner for all unit
tests (to enable them to be run from the command line outside of
Ant or Eclipse).
(Bug #3554)
Added encoding names that are recognized on some JVMs to fix case where they were reverse-mapped to MySQL encoding names incorrectly. (Bug #3554)
Made StringRegressionTest 4.1-unicode aware.
(Bug #3520)
Fixed regression in
PreparedStatement.setString() and eastern
character encodings.
(Bug #3520)
DBMD.getSQLStateType() returns incorrect
value.
(Bug #3520)
Renamed StringUtils.escapeSJISByteStream() to
more appropriate
escapeEasternUnicodeByteStream().
(Bug #3511)
StringUtils.escapeSJISByteStream() not
covering all eastern double-byte charsets correctly.
(Bug #3511)
Return creating statement for ResultSets
created by getGeneratedKeys().
(Bug #2957)
Use SET character_set_results during
initialization to enable any charset to be returned to the
driver for result sets.
(Bug #2670)
Don't truncate BLOB or
CLOB values when using
setBytes() and
setBinary/CharacterStream().
(Bug #2670)
Dynamically configure character set mappings for field-level
character sets on MySQL-4.1.0 and newer using
SHOW COLLATION when connecting.
(Bug #2670)
Map binary character set to
US-ASCII to support
DATETIME charset recognition for
servers >= 4.1.2.
(Bug #2670)
Use charsetnr returned during connect to
encode queries before issuing SET NAMES on
MySQL >= 4.1.0.
(Bug #2670)
Add helper methods to ResultSetMetaData
(getColumnCharacterEncoding() and
getColumnCharacterSet()) to permit end users
to see what charset the driver thinks it should be using for the
column.
(Bug #2670)
Only set character_set_results
for MySQL >= 4.1.0.
(Bug #2670)
Allow url parameter for
MysqlDataSource and
MysqlConnectionPool
DataSource so that passing of other
properties is possible from inside appservers.
Don't escape SJIS/GBK/BIG5 when using MySQL-4.1 or newer.
Backport documentation tooling from 3.1 branch.
Added failOverReadOnly property, to enable
the user to configure the state of the connection
(read-only/writable) when failed over.
Allow java.util.Date to be sent in as
parameter to PreparedStatement.setObject(),
converting it to a Timestamp to maintain full
precision. .
(Bug #103)
Add unsigned attribute to
DatabaseMetaData.getColumns() output in the
TYPE_NAME column.
Map duplicate key and foreign key errors to SQLState of
23000.
Backported “change user” and “reset server
state” functionality from 3.1 branch, to enable clients
of MysqlConnectionPoolDataSource to reset
server state on getConnection() on a pooled
connection.
Bugs Fixed
Return java.lang.Double for
FLOAT type from
ResultSetMetaData.getColumnClassName().
(Bug #2855)
Return [B instead of
java.lang.Object for
BINARY,
VARBINARY and
LONGVARBINARY types from
ResultSetMetaData.getColumnClassName() (JDBC
compliance).
(Bug #2855)
Issue connection events on all instances created from a
ConnectionPoolDataSource.
(Bug #2855)
Return java.lang.Integer for
TINYINT and
SMALLINT types from
ResultSetMetaData.getColumnClassName().
(Bug #2852)
Added useUnbufferedInput parameter, and now
use it by default (due to JVM issue
http://developer.java.sun.com/developer/bugParade/bugs/4401235.html)
(Bug #2578)
Fixed failover always going to last host in list. (Bug #2578)
Detect on/off or
1, 2, 3
form of lower_case_table_names
value on server.
(Bug #2578)
AutoReconnect time was growing faster than
exponentially.
(Bug #2447)
Trigger a SET NAMES utf8 when encoding is
forced to utf8 or
utf-8 using the
characterEncoding property. Previously, only
the Java-style encoding name of utf-8 would
trigger this.
Bugs Fixed
Enable caching of the parsing stage of prepared statements using
the cachePrepStmts,
prepStmtCacheSize, and
prepStmtCacheSqlLimit properties (disabled by
default).
(Bug #2006)
Fixed security exception when used in Applets (applets can't
read the system property file.encoding which
is needed for LOAD
DATA LOCAL INFILE).
(Bug #2006)
Speed up parsing of PreparedStatements, try
to use one-pass whenever possible.
(Bug #2006)
Fixed exception Unknown character set
'danish' on connect with JDK-1.4.0
(Bug #2006)
Fixed mappings in SQLError to report deadlocks with SQLStates of
41000.
(Bug #2006)
Removed static synchronization bottleneck from instance factory
method of SingleByteCharsetConverter.
(Bug #2006)
Removed static synchronization bottleneck from
PreparedStatement.setTimestamp().
(Bug #2006)
ResultSet.findColumn() should use first
matching column name when there are duplicate column names in
SELECT query (JDBC-compliance).
(Bug #2006)
maxRows property would affect internal
statements, so check it for all statement creation internal to
the driver, and set to 0 when it is not.
(Bug #2006)
Use constants for SQLStates. (Bug #2006)
Map charset ko18_ru to
ko18r when connected to MySQL-4.1.0 or newer.
(Bug #2006)
Ensure that Buffer.writeString() saves room
for the \0.
(Bug #2006)
ArrayIndexOutOfBounds when parameter number
== number of parameters + 1.
(Bug #1958)
Connection property maxRows not honored.
(Bug #1933)
Statements being created too many times in
DBMD.extractForeignKeyFromCreateTable().
(Bug #1925)
Support escape sequence {fn convert ... }. (Bug #1914)
Implement ResultSet.updateClob().
(Bug #1913)
Autoreconnect code didn't set catalog upon reconnect if it had been changed. (Bug #1913)
ResultSet.getObject() on
TINYINT and
SMALLINT columns should return
Java type Integer.
(Bug #1913)
Added more descriptive error message Server
Configuration Denies Access to DataSource, as well as
retrieval of message from server.
(Bug #1913)
ResultSetMetaData.isCaseSensitive() returned
wrong value for
CHAR/VARCHAR
columns.
(Bug #1913)
Added alwaysClearStream connection property,
which causes the driver to always empty any remaining data on
the input stream before each query.
(Bug #1913)
DatabaseMetaData.getSystemFunction()
returning bad function VResultsSion.
(Bug #1775)
Foreign Keys column sequence is not consistent in
DatabaseMetaData.getImported/Exported/CrossReference().
(Bug #1731)
Fix for ArrayIndexOutOfBounds exception when
using Statement.setMaxRows().
(Bug #1695)
Subsequent call to ResultSet.updateFoo()
causes NPE if result set is not updatable.
(Bug #1630)
Fix for 4.1.1-style authentication with no password. (Bug #1630)
Cross-database updatable result sets are not checked for updatability correctly. (Bug #1592)
DatabaseMetaData.getColumns() should return
Types.LONGVARCHAR for MySQL
LONGTEXT type.
(Bug #1592)
Fixed regression of
Statement.getGeneratedKeys() and
REPLACE statements.
(Bug #1576)
Barge blobs and split packets not being read correctly. (Bug #1576)
Backported fix for aliased tables and
UpdatableResultSets in
checkUpdatability() method from 3.1 branch.
(Bug #1534)
“Friendlier” exception message for
PacketTooLargeException.
(Bug #1534)
Don't count quoted IDs when inside a 'string' in
PreparedStatement parsing.
(Bug #1511)
Bugs Fixed
ResultSet.get/setString mashing char 127.
(Bug #1247)
Added property to “clobber” streaming results, by
setting the clobberStreamingResults property
to true (the default is
false). This will cause a
“streaming” ResultSet to be
automatically closed, and any outstanding data still streaming
from the server to be discarded if another query is executed
before all the data has been read from the server.
(Bug #1247)
Added com.mysql.jdbc.util.BaseBugReport to
help creation of testcases for bug reports.
(Bug #1247)
Backported authentication changes for 4.1.1 and newer from 3.1 branch. (Bug #1247)
Made databaseName,
portNumber, and serverName
optional parameters for
MysqlDataSourceFactory.
(Bug #1246)
Optimized CLOB.setChracterStream().
(Bug #1131)
Fixed CLOB.truncate().
(Bug #1130)
Fixed deadlock issue with
Statement.setMaxRows().
(Bug #1099)
DatabaseMetaData.getColumns() getting
confused about the keyword “set” in character
columns.
(Bug #1099)
Clip +/- INF (to smallest and largest representative values for
the type in MySQL) and NaN (to 0) for
setDouble/setFloat(), and
issue a warning on the statement when the server does not
support +/- INF or NaN.
(Bug #884)
Don't fire connection closed events when closing pooled
connections, or on
PooledConnection.getConnection() with already
open connections.
(Bug #884)
Double-escaping of '\' when charset is SJIS
or GBK and '\' appears in nonescaped input.
(Bug #879)
When emptying input stream of unused rows for
“streaming” result sets, have the current thread
yield() every 100 rows to not monopolize CPU
time.
(Bug #879)
Issue exception on
ResultSet.get
on empty result set (wasn't caught in some cases).
(Bug #848)XXX()
Don't hide messages from exceptions thrown in I/O layers. (Bug #848)
Fixed regression in large split-packet handling. (Bug #848)
Better diagnostic error messages in exceptions for “streaming” result sets. (Bug #848)
Don't change timestamp TZ twice if
useTimezone==true.
(Bug #774)
Don't wrap SQLExceptions in
RowDataDynamic.
(Bug #688)
Don't try and reset isolation level on reconnect if MySQL doesn't support them. (Bug #688)
The insertRow in an
UpdatableResultSet is now loaded with the
default column values when moveToInsertRow()
is called.
(Bug #688)
DatabaseMetaData.getColumns() wasn't
returning NULL for default values that are
specified as NULL.
(Bug #688)
Change default statement type/concurrency to
TYPE_FORWARD_ONLY and
CONCUR_READ_ONLY (spec compliance).
(Bug #688)
Fix UpdatableResultSet to return values for
get when on
insert row.
(Bug #675)XXX()
Support InnoDB constraint names when
extracting foreign key information in
DatabaseMetaData (implementing ideas from
Parwinder Sekhon).
(Bug #664, Bug #517)
Backported 4.1 protocol changes from 3.1 branch (server-side SQL states, new field information, larger client capability flags, connect-with-database, and so forth). (Bug #664, Bug #517)
refreshRow didn't work when primary key
values contained values that needed to be escaped (they ended up
being doubly escaped).
(Bug #661)
Fixed ResultSet.previous() behavior to move
current position to before result set when on first row of
result set.
(Bug #496)
Fixed Statement and
PreparedStatement issuing bogus queries when
setMaxRows() had been used and a
LIMIT clause was present in the query.
(Bug #496)
Faster date handling code in ResultSet and
PreparedStatement (no longer uses
Date methods that synchronize on static
calendars).
Fixed test for end of buffer in
Buffer.readString().
Bugs Fixed
Fixed SJIS encoding bug, thanks to Naoto Sato. (Bug #378)
Fix problem detecting server character set in some cases. (Bug #378)
Allow multiple calls to Statement.close().
(Bug #378)
Return correct number of generated keys when using
REPLACE statements.
(Bug #378)
Unicode character 0xFFFF in a string would cause the driver to
throw an ArrayOutOfBoundsException. .
(Bug #378)
Fix row data decoding error when using very large packets. (Bug #378)
Optimized row data decoding. (Bug #378)
Issue exception when operating on an already closed prepared statement. (Bug #378)
Optimized usage of EscapeProcessor.
(Bug #378)
Use JVM charset with file names and LOAD DATA [LOCAL]
INFILE.
Fix infinite loop with Connection.cleanup().
Changed Ant target compile-core to
compile-driver, and made testsuite
compilation a separate target.
Fixed result set not getting set for
Statement.executeUpdate(), which affected
getGeneratedKeys() and
getUpdateCount() in some cases.
Return list of generated keys when using multi-value
INSERTS with
Statement.getGeneratedKeys().
Allow bogus URLs in Driver.getPropertyInfo().
Bugs Fixed
Fixed charset issues with database metadata (charset was not getting set correctly).
You can now toggle profiling on/off using
Connection.setProfileSql(boolean).
4.1 Column Metadata fixes.
Fixed MysqlPooledConnection.close() calling
wrong event type.
Fixed StringIndexOutOfBoundsException in
PreparedStatement.setClob().
IOExceptions during a transaction now cause
the Connection to be closed.
Remove synchronization from Driver.connect()
and Driver.acceptsUrl().
Fixed missing conversion for YEAR
type in
ResultSetMetaData.getColumnTypeName().
Updatable ResultSets can now be created for
aliased tables/columns when connected to MySQL-4.1 or newer.
Fixed LOAD DATA LOCAL
INFILE bug when file >
max_allowed_packet.
Don't pick up indexes that start with pri as
primary keys for DBMD.getPrimaryKeys().
Ensure that packet size from
alignPacketSize() does not exceed
max_allowed_packet (JVM bug)
Don't reset Connection.isReadOnly() when
autoReconnecting.
Fixed escaping of 0x5c ('\') character for
GBK and Big5 charsets.
Fixed ResultSet.getTimestamp() when
underlying field is of type DATE.
Throw SQLExceptions when trying to do
operations on a forcefully closed Connection
(that is, when a communication link failure occurs).
Bugs Fixed
Backported 4.1 charset field info changes from Connector/J 3.1.
Fixed Statement.setMaxRows() to stop sending
LIMIT type queries when not needed
(performance).
Fixed DBMD.getTypeInfo() and
DBMD.getColumns() returning different value
for precision in TEXT and
BLOB types.
Fixed SQLExceptions getting swallowed on
initial connect.
Fixed ResultSetMetaData to return
"" when catalog not known. Fixes
NullPointerExceptions with Sun's
CachedRowSet.
Allow ignoring of warning for “non transactional
tables” during rollback (compliance/usability) by setting
ignoreNonTxTables property to
true.
Clean up Statement query/method mismatch
tests (that is, INSERT not
permitted with .executeQuery()).
Fixed ResultSetMetaData.isWritable() to
return correct value.
More checks added in ResultSet traversal
method to catch when in closed state.
Implemented Blob.setBytes(). You still need
to pass the resultant Blob back into an
updatable ResultSet or
PreparedStatement to persist the changes,
because MySQL does not support “locators”.
Add “window” of different NULL
sorting behavior to
DBMD.nullsAreSortedAtStart (4.0.2 to 4.0.10,
true; otherwise, no).
Bugs Fixed
Fixed ResultSet.isBeforeFirst() for empty
result sets.
Added missing
LONGTEXT type to
DBMD.getColumns().
Implemented an empty TypeMap for
Connection.getTypeMap() so that some
third-party apps work with MySQL (IBM WebSphere 5.0 Connection
pool).
Added update options for foreign key metadata.
Fixed Buffer.fastSkipLenString() causing
ArrayIndexOutOfBounds exceptions with some
queries when unpacking fields.
Quote table names in
DatabaseMetaData.getColumns(),
getPrimaryKeys(),
getIndexInfo(),
getBestRowIdentifier().
Retrieve TX_ISOLATION from database for
Connection.getTransactionIsolation() when the
MySQL version supports it, instead of an instance variable.
Greatly reduce memory required for
setBinaryStream() in
PreparedStatements.
Bugs Fixed
Streamlined character conversion and byte[]
handling in PreparedStatements for
setByte().
Fixed PreparedStatement.executeBatch()
parameter overwriting.
Added quoted identifiers to database names for
Connection.setCatalog.
Added support for 4.0.8-style large packets.
Reduce memory footprint of PreparedStatements
by sharing outbound packet with MysqlIO.
Added strictUpdates property to enable
control of amount of checking for “correctness” of
updatable result sets. Set this to false if
you want faster updatable result sets and you know that you
create them from SELECT
statements on tables with primary keys and that you have
selected all primary keys in your query.
Added support for quoted identifiers in
PreparedStatement parser.
Bugs Fixed
Allow user to alter behavior of Statement/
PreparedStatement.executeBatch() using
continueBatchOnError property (defaults to
true).
More robust escape tokenizer: Recognize --
comments, and permit nested escape sequences (see
testsuite.EscapeProcessingTest).
Fixed Buffer.isLastDataPacket() for 4.1 and
newer servers.
NamedPipeSocketFactory now works (only
intended for Windows), see README for
instructions.
Changed charsToByte in
SingleByteCharConverter to be nonstatic.
Use nonaliased table/column names and database names to fully
qualify tables and columns in
UpdatableResultSet (requires MySQL-4.1 or
newer).
LOAD DATA LOCAL INFILE ... now works, if your
server is configured to permit it. Can be turned off with the
allowLoadLocalInfile property (see the
README).
Implemented Connection.nativeSQL().
Fixed ResultSetMetaData.getColumnTypeName()
returning BLOB for
TEXT and
TEXT for
BLOB types.
Fixed charset handling in Fields.java.
Because of above, implemented
ResultSetMetaData.isAutoIncrement() to use
Field.isAutoIncrement().
Substitute '?' for unknown character
conversions in single-byte character sets instead of
'\0'.
Added CLIENT_LONG_FLAG to be able to get more
column flags (isAutoIncrement() being the
most important).
Honor lower_case_table_names
when enabled in the server when doing table name comparisons in
DatabaseMetaData methods.
DBMD.getImported/ExportedKeys() now handles
multiple foreign keys per table.
More robust implementation of updatable result sets. Checks that all primary keys of the table have been selected.
Some MySQL-4.1 protocol support (extended field info from selects).
Check for connection closed in more
Connection methods
(createStatement,
prepareStatement,
setTransactionIsolation,
setAutoCommit).
Fixed ResultSetMetaData.getPrecision()
returning incorrect values for some floating-point types.
Changed SingleByteCharConverter to use lazy
initialization of each converter.
Bugs Fixed
Implemented Clob.setString().
Added com.mysql.jdbc.MiniAdmin class, which
enables you to send shutdown command to MySQL
server. This is intended to be used when
“embedding” Java and MySQL server together in an
end-user application.
Added SSL support. See README for
information on how to use it.
All DBMD result set columns describing
schemas now return NULL to be more compliant
with the behavior of other JDBC drivers for other database
systems (MySQL does not support schemas).
Use SHOW CREATE TABLE when
possible for determining foreign key information for
DatabaseMetaData. Also enables cascade
options for DELETE information to
be returned.
Implemented Clob.setCharacterStream().
Failover and autoReconnect work only when the
connection is in an autoCommit(false) state,
to stay transaction-safe.
Fixed DBMD.supportsResultSetConcurrency() so
that it returns true for
ResultSet.TYPE_SCROLL_INSENSITIVE and
ResultSet.CONCUR_READ_ONLY or
ResultSet.CONCUR_UPDATABLE.
Implemented Clob.setAsciiStream().
Removed duplicate code from
UpdatableResultSet (it can be inherited from
ResultSet, the extra code for each method to
handle updatability I thought might someday be necessary has not
been needed).
Fixed UnsupportedEncodingException thrown
when “forcing” a character encoding using
properties.
Fixed incorrect conversion in
ResultSet.getLong().
Implemented ResultSet.updateBlob().
Removed some not-needed temporary object creation by smarter use
of Strings in
EscapeProcessor,
Connection and
DatabaseMetaData classes.
Escape 0x5c character in strings for the SJIS
charset.
PreparedStatement now honors stream lengths
in setBinary/Ascii/Character Stream() unless you set the
connection property
useStreamLengthsInPrepStmts to
false.
Fixed issue with updatable result sets and
PreparedStatements not working.
Fixed start position off-by-1 error in
Clob.getSubString().
Added connectTimeout parameter that enables
users of JDK-1.4 and newer to specify a maximum time to wait to
establish a connection.
Fixed various non-ASCII character encoding issues.
Fixed ResultSet.isLast() for empty result
sets (should return false).
Added driver property useHostsInPrivileges.
Defaults to true. Affects whether or not
@hostname will be used in
DBMD.getColumn/TablePrivileges.
Fixed
ResultSet.setFetchDirection(FETCH_UNKNOWN).
Added queriesBeforeRetryMaster property that
specifies how many queries to issue when failed over before
attempting to reconnect to the master (defaults to 50).
Fixed issue when calling
Statement.setFetchSize() when using arbitrary
values.
Properly restore connection properties when autoReconnecting or
failing-over, including autoCommit state, and
isolation level.
Implemented Clob.truncate().
Bugs Fixed
Charsets now automatically detected. Optimized code for single-byte character set conversion.
Fixed RowDataStatic.getAt() off-by-one bug.
Fixed ResultSet.getRow() off-by-one bug.
Massive code clean-up to follow Java coding conventions (the time had come).
Implemented ResultSet.getCharacterStream().
Added limited Clob functionality
(ResultSet.getClob(),
PreparedStatement.setClob(),
PreparedStatement.setObject(Clob).
Connection.isClosed() no longer
“pings” the server.
Connection.close() issues
rollback() when
getAutoCommit() is false.
Added socketTimeout parameter to URL.
Added LOCAL TEMPORARY to table types in
DatabaseMetaData.getTableTypes().
Added paranoid parameter, which sanitizes
error messages by removing “sensitive” information
from them (such as host names, ports, or user names), as well as
clearing “sensitive” data structures when possible.
Bugs Fixed
General source-code cleanup.
The driver now only works with JDK-1.2 or newer.
Fix and sort primary key names in DBMetaData
(SF bugs 582086 and 582086).
ResultSet.getTimestamp() now works for
DATE types (SF bug 559134).
Float types now reported as
java.sql.Types.FLOAT (SF bug 579573).
Support for streaming (row-by-row) result sets (see
README) Thanks to Doron.
Testsuite now uses Junit (which you can get from http://www.junit.org.
JDBC Compliance: Passes all tests besides stored procedure tests.
ResultSet.getDate/Time/Timestamp now
recognizes all forms of invalid values that have been set to all
zeros by MySQL (SF bug 586058).
Added multi-host failover support (see
README).
Repackaging: New driver name is
com.mysql.jdbc.Driver, old name still works,
though (the driver is now provided by MySQL-AB).
Support for large packets (new addition to MySQL-4.0 protocol),
see README for more information.
Better checking for closed connections in
Statement and
PreparedStatement.
Performance improvements in string handling and field metadata creation (lazily instantiated) contributed by Alex Twisleton-Wykeham-Fiennes.
JDBC-3.0 functionality including
Statement/PreparedStatement.getGeneratedKeys()
and ResultSet.getURL().
Overall speed improvements using controlling transient object
creation in MysqlIO class when reading
packets.
!!! LICENSE CHANGE !!! The
driver is now GPL. If you need non-GPL licenses, please contact
me <mark@mysql.com>.
Performance enhancements: Driver is now 50–100% faster in most situations, and creates fewer temporary objects.
Bugs Fixed
ResultSet.getDouble() now uses code built
into JDK to be more precise (but slower).
Fixed typo for relaxAutoCommit parameter.
LogicalHandle.isClosed() calls through to
physical connection.
Added SQL profiling (to STDERR). Set
profileSql=true in your JDBC URL. See
README for more information.
PreparedStatement now releases resources on
.close(). (SF bug 553268)
More code cleanup.
Quoted identifiers not used if server version does not support
them. Also, if server started with
--ansi or
--sql-mode=ANSI_QUOTES,
“"” will be used as an
identifier quote character, otherwise
“'” will be used.
Bugs Fixed
Fixed unicode chars being read incorrectly. (SF bug 541088)
Faster blob escaping for PrepStmt.
Added setURL() to
MySQLXADataSource. (SF bug 546019)
Added set/getPortNumber()
to DataSource(s). (SF bug 548167)
PreparedStatement.toString() fixed. (SF bug
534026)
More code cleanup.
Rudimentary version of
Statement.getGeneratedKeys() from JDBC-3.0
now implemented (you need to be using JDK-1.4 for this to work,
I believe).
DBMetaData.getIndexInfo() - bad PAGES fixed.
(SF BUG 542201)
ResultSetMetaData.getColumnClassName() now
implemented.
Bugs Fixed
Fixed testsuite.Traversal
afterLast() bug, thanks to Igor Lastric.
Added new types to getTypeInfo(), fixed
existing types thanks to Al Davis and Kid Kalanon.
Fixed time zone off-by-1-hour bug in
PreparedStatement (538286, 528785).
Added identifier quoting to all
DatabaseMetaData methods that need them
(should fix 518108).
Added support for BIT types
(51870) to PreparedStatement.
ResultSet.insertRow() should now detect
auto_increment fields in most cases and use that value in the
new row. This detection will not work in multi-valued keys,
however, due to the fact that the MySQL protocol does not return
this information.
Relaxed synchronization in all classes, should fix 520615 and 520393.
DataSources - fixed setUrl
bug (511614, 525565), wrong datasource class name (532816,
528767).
Added support for YEAR type
(533556).
Fixes for ResultSet updatability in
PreparedStatement.
ResultSet: Fixed updatability (values being
set to null if not updated).
Added getTable/ColumnPrivileges() to DBMD
(fixes 484502).
Added getIdleFor() method to
Connection and
MysqlLogicalHandle.
ResultSet.refreshRow() implemented.
Fixed getRow() bug (527165) in
ResultSet.
General code cleanup.
Bugs Fixed
Full synchronization of Statement.java.
Fixed missing DELETE_RULE value in
DBMD.getImported/ExportedKeys() and
getCrossReference().
More changes to fix Unexpected end of input
stream errors when reading
BLOB values. This should be the
last fix.
Bugs Fixed
Fixed null-pointer-exceptions when using
MysqlConnectionPoolDataSource with Websphere
4 (bug 505839).
Fixed spurious Unexpected end of input stream
errors in MysqlIO (bug 507456).
Bugs Fixed
Fixed extra memory allocation in
MysqlIO.readPacket() (bug 488663).
Added detection of network connection being closed when reading packets (thanks to Todd Lizambri).
Fixed casting bug in PreparedStatement (bug
488663).
DataSource implementations moved to
org.gjt.mm.mysql.jdbc2.optional package, and
(initial) implementations of
PooledConnectionDataSource and
XADataSource are in place (thanks to Todd
Wolff for the implementation and testing of
PooledConnectionDataSource with IBM WebSphere
4).
Fixed quoting error with escape processor (bug 486265).
Removed concatenation support from driver (the
|| operator), as older versions of VisualAge
seem to be the only thing that use it, and it conflicts with the
logical || operator. You will need to start
mysqld with the
--ansi flag to use the
|| operator as concatenation (bug 491680).
Ant build was corrupting included
jar files, fixed (bug 487669).
Report batch update support through
DatabaseMetaData (bug 495101).
Implementation of
DatabaseMetaData.getExported/ImportedKeys()
and getCrossReference().
Fixed off-by-one-hour error in
PreparedStatement.setTimestamp() (bug
491577).
Full synchronization on methods modifying instance and class-shared references, driver should be entirely thread-safe now (please let me know if you have problems).
Bugs Fixed
XADataSource/ConnectionPoolDataSource
code (experimental)
DatabaseMetaData.getPrimaryKeys() and
getBestRowIdentifier() are now more robust in
identifying primary keys (matches regardless of case or
abbreviation/full spelling of Primary Key in
Key_type column).
Batch updates now supported (thanks to some inspiration from Daniel Rall).
PreparedStatement.setAnyNumericType() now
handles positive exponents correctly (adds +
so MySQL can understand it).
Bugs Fixed
Character sets read from database if
useUnicode=true and
characterEncoding is not set. (thanks to
Dmitry Vereshchagin)
Initial transaction isolation level read from database (if available). (thanks to Dmitry Vereshchagin)
Fixed PreparedStatement generating SQL that
would end up with syntax errors for some queries.
PreparedStatement.setCharacterStream() now
implemented
Capitalize type names when
capitalizeTypeNames=true is passed in URL or
properties (for WebObjects. (thanks to Anjo Krank)
ResultSet.getBlob() now returns
null if column value was
null.
Fixed ResultSetMetaData.getPrecision()
returning one less than actual on newer versions of MySQL.
Fixed dangling socket problem when in high availability
(autoReconnect=true) mode, and finalizer for
Connection will close any dangling sockets on
GC.
Fixed time zone issue in
PreparedStatement.setTimestamp(). (thanks to
Erik Olofsson)
PreparedStatement.setDouble() now uses full-precision doubles (reverting a fix made earlier to truncate them).
Fixed
DatabaseMetaData.supportsTransactions(), and
supportsTransactionIsolationLevel() and
getTypeInfo()
SQL_DATETIME_SUB and
SQL_DATA_TYPE fields not being readable.
Updatable result sets now correctly handle
NULL values in fields.
PreparedStatement.setBoolean() will use 1/0 for values if your MySQL version is 3.21.23 or higher.
Fixed ResultSet.isAfterLast() always
returning false.
Bugs Fixed
Fixed PreparedStatement parameter checking.
Fixed case-sensitive column names in
ResultSet.java.
Bugs Fixed
ResultSet.insertRow() works now, even if not
all columns are set (they will be set to
NULL).
Added Byte to
PreparedStatement.setObject().
Fixed data parsing of TIMESTAMP
values with 2-digit years.
Added ISOLATION level support to
Connection.setIsolationLevel()
DataBaseMetaData.getCrossReference() no
longer ArrayIndexOOB.
ResultSet.getBoolean() now recognizes
-1 as true.
ResultSet has +/-Inf/inf support.
getObject() on ResultSet
correctly does
TINYINT->Byte
and
SMALLINT->Short.
Fixed ArrayIndexOutOfBounds when sending
large BLOB queries. (Max size
packet was not being set)
Fixed NPE on
PreparedStatement.executeUpdate() when all
columns have not been set.
Fixed ResultSet.getBlob()
ArrayIndex out-of-bounds.
Bugs Fixed
Fixed composite key problem with updatable result sets.
Faster ASCII string operations.
Fixed off-by-one error in java.sql.Blob
implementation code.
Fixed incorrect detection of
MAX_ALLOWED_PACKET, so sending large blobs
should work now.
Added detection of -/+INF for doubles.
Added ultraDevHack URL parameter, set to
true to enable (broken) Macromedia UltraDev
to use the driver.
Implemented getBigDecimal() without scale
component for JDBC2.
Bugs Fixed
Columns that are of type TEXT now
return as Strings when you use
getObject().
Cleaned up exception handling when driver connects.
Fixed RSMD.isWritable() returning wrong
value. Thanks to Moritz Maass.
DatabaseMetaData.getPrimaryKeys() now works
correctly with respect to key_seq. Thanks to
Brian Slesinsky.
Fixed many JDBC-2.0 traversal, positioning bugs, especially with respect to empty result sets. Thanks to Ron Smits, Nick Brook, Cessar Garcia and Carlos Martinez.
No escape processing is done on
PreparedStatements anymore per JDBC spec.
Fixed some issues with updatability support in
ResultSet when using multiple primary keys.
Fixes to ResultSet for insertRow() - Thanks to Cesar Garcia
Fix to Driver to recognize JDBC-2.0 by loading a JDBC-2.0 class, instead of relying on JDK version numbers. Thanks to John Baker.
Fixed ResultSet to return correct row numbers
Statement.getUpdateCount() now returns rows matched, instead of rows actually updated, which is more SQL-92 like.
10-29-99
Statement/PreparedStatement.getMoreResults() bug fixed. Thanks to Noel J. Bergman.
Added Short as a type to PreparedStatement.setObject(). Thanks to Jeff Crowder
Driver now automagically configures maximum/preferred packet sizes by querying server.
Autoreconnect code uses fast ping command if server supports it.
Fixed various bugs with respect to packet sizing when reading from the server and when alloc'ing to write to the server.
Now compiles under JDK-1.2. The driver supports both JDK-1.1 and JDK-1.2 at the same time through a core set of classes. The driver will load the appropriate interface classes at runtime by figuring out which JVM version you are using.
Fixes for result sets with all nulls in the first row. (Pointed out by Tim Endres)
Fixes to column numbers in SQLExceptions in ResultSet (Thanks to Blas Rodriguez Somoza)
The database no longer needs to specified to connect. (Thanks to Christian Motschke)
Better Documentation (in progress), in doc/mm.doc/book1.html
DBMD now permits null for a column name pattern (not in spec), which it changes to '%'.
DBMD now has correct types/lengths for getXXX().
ResultSet.getDate(), getTime(), and getTimestamp() fixes. (contributed by Alan Wilken)
EscapeProcessor now handles \{ \} and { or } inside quotation marks correctly. (thanks to Alik for some ideas on how to fix it)
Fixes to properties handling in Connection. (contributed by Juho Tikkala)
ResultSet.getObject() now returns null for NULL columns in the table, rather than bombing out. (thanks to Ben Grosman)
ResultSet.getObject() now returns Strings for types from MySQL that it doesn't know about. (Suggested by Chris Perdue)
Removed DataInput/Output streams, not needed, 1/2 number of method calls per IO operation.
Use default character encoding if one is not specified. This is a work-around for broken JVMs, because according to spec, EVERY JVM must support "ISO8859_1", but they do not.
Fixed Connection to use the platform character encoding instead of "ISO8859_1" if one isn't explicitly set. This fixes problems people were having loading the character- converter classes that didn't always exist (JVM bug). (thanks to Fritz Elfert for pointing out this problem)
Changed MysqlIO to re-use packets where possible to reduce memory usage.
Fixed escape-processor bugs pertaining to {} inside quotation marks.
Fixed character-set support for non-Javasoft JVMs (thanks to many people for pointing it out)
Fixed ResultSet.getBoolean() to recognize 'y' & 'n' as well as '1' & '0' as boolean flags. (thanks to Tim Pizey)
Fixed ResultSet.getTimestamp() to give better performance. (thanks to Richard Swift)
Fixed getByte() for numeric types. (thanks to Ray Bellis)
Fixed DatabaseMetaData.getTypeInfo() for DATE type. (thanks to Paul Johnston)
Fixed EscapeProcessor for "fn" calls. (thanks to Piyush Shah at locomotive.org)
Fixed EscapeProcessor to not do extraneous work if there are no escape codes. (thanks to Ryan Gustafson)
Fixed Driver to parse URLs of the form "jdbc:mysql://host:port" (thanks to Richard Lobb)
Fixed Timestamps for PreparedStatements
Fixed null pointer exceptions in RSMD and RS
Re-compiled with jikes for valid class files (thanks ms!)
Fixed escape processor to deal with unmatched { and } (thanks to Craig Coles)
Fixed escape processor to create more portable (between DATETIME and TIMESTAMP types) representations so that it will work with BETWEEN clauses. (thanks to Craig Longman)
MysqlIO.quit() now closes the socket connection. Before, after many failed connections some OS's would run out of file descriptors. (thanks to Michael Brinkman)
Fixed NullPointerException in Driver.getPropertyInfo. (thanks to Dave Potts)
Fixes to MysqlDefs to allow all *text fields to be retrieved as Strings. (thanks to Chris at Leverage)
Fixed setDouble in PreparedStatement for large numbers to avoid sending scientific notation to the database. (thanks to J.S. Ferguson)
Fixed getScale() and getPrecision() in RSMD. (contrib'd by James Klicman)
Fixed getObject() when field was DECIMAL or NUMERIC (thanks to Bert Hobbs)
DBMD.getTables() bombed when passed a null table-name pattern. Fixed. (thanks to Richard Lobb)
Added check for "client not authorized" errors during connect. (thanks to Hannes Wallnoefer)
Result set rows are now byte arrays. Blobs and Unicode work bidirectonally now. The useUnicode and encoding options are implemented now.
Fixes to PreparedStatement to send binary set by setXXXStream to be sent untouched to the MySQL server.
Fixes to getDriverPropertyInfo().
Changed all ResultSet fields to Strings, this should allow Unicode to work, but your JVM must be able to convert between the character sets. This should also make reading data from the server be a bit quicker, because there is now no conversion from StringBuffer to String.
Changed PreparedStatement.streamToString() to be more efficient (code from Uwe Schaefer).
URL parsing is more robust (throws SQL exceptions on errors rather than NullPointerExceptions)
PreparedStatement now can convert Strings to Time/Date values using setObject() (code from Robert Currey).
IO no longer hangs in Buffer.readInt(), that bug was introduced in 1.1d when changing to all byte-arrays for result sets. (Pointed out by Samo Login)
Fixes to DatabaseMetaData to allow both IBM VA and J-Builder to work. Let me know how it goes. (thanks to Jac Kersing)
Fix to ResultSet.getBoolean() for NULL strings (thanks to Barry Lagerweij)
Beginning of code cleanup, and formatting. Getting ready to branch this off to a parallel JDBC-2.0 source tree.
Added "final" modifier to critical sections in MysqlIO and Buffer to allow compiler to inline methods for speed.
9-29-98
If object references passed to setXXX() in PreparedStatement are null, setNull() is automatically called for you. (Thanks for the suggestion goes to Erik Ostrom)
setObject() in PreparedStatement will now attempt to write a serialized representation of the object to the database for objects of Types.OTHER and objects of unknown type.
Util now has a static method readObject() which given a ResultSet and a column index will re-instantiate an object serialized in the above manner.
Got rid of "ugly hack" in MysqlIO.nextRow(). Rather than catch an exception, Buffer.isLastDataPacket() was fixed.
Connection.getCatalog() and Connection.setCatalog() should work now.
Statement.setMaxRows() works, as well as setting by property maxRows. Statement.setMaxRows() overrides maxRows set using properties or url parameters.
Automatic re-connection is available. Because it has to "ping" the database before each query, it is turned off by default. To use it, pass in "autoReconnect=true" in the connection URL. You may also change the number of reconnect tries, and the initial timeout value using "maxReconnects=n" (default 3) and "initialTimeout=n" (seconds, default 2) parameters. The timeout is an exponential backoff type of timeout; for example, if you have initial timeout of 2 seconds, and maxReconnects of 3, then the driver will timeout 2 seconds, 4 seconds, then 16 seconds between each re-connection attempt.
Fixed handling of blob data in Buffer.java
Fixed bug with authentication packet being sized too small.
The JDBC Driver is now under the LGPL
8-14-98
Fixed Buffer.readLenString() to correctly read data for BLOBS.
Fixed PreparedStatement.stringToStream to correctly read data for BLOBS.
Fixed PreparedStatement.setDate() to not add a day. (above fixes thanks to Vincent Partington)
Added URL parameter parsing (?user=... and so forth).
Big news! New package name. Tim Endres from ICE Engineering is starting a new source tree for GNU GPL'd Java software. He's graciously given me the org.gjt.mm package directory to use, so now the driver is in the org.gjt.mm.mysql package scheme. I'm "legal" now. Look for more information on Tim's project soon.
Now using dynamically sized packets to reduce memory usage when sending commands to the DB.
Small fixes to getTypeInfo() for parameters, and so forth.
DatabaseMetaData is now fully implemented. Let me know if these drivers work with the various IDEs out there. I've heard that they're working with JBuilder right now.
Added JavaDoc documentation to the package.
Package now available in .zip or .tar.gz.
Implemented getTypeInfo(). Connection.rollback() now throws an SQLException per the JDBC spec.
Added PreparedStatement that supports all JDBC API methods for PreparedStatement including InputStreams. Please check this out and let me know if anything is broken.
Fixed a bug in ResultSet that would break some queries that only returned 1 row.
Fixed bugs in DatabaseMetaData.getTables(), DatabaseMetaData.getColumns() and DatabaseMetaData.getCatalogs().
Added functionality to Statement that enables executeUpdate() to store values for IDs that are automatically generated for AUTO_INCREMENT fields. Basically, after an executeUpdate(), look at the SQLWarnings for warnings like "LAST_INSERTED_ID = 'some number', COMMAND = 'your SQL query'". If you are using AUTO_INCREMENT fields in your tables and are executing a lot of executeUpdate()s on one Statement, be sure to clearWarnings() every so often to save memory.
Split MysqlIO and Buffer to separate classes. Some ClassLoaders gave an IllegalAccess error for some fields in those two classes. Now mm.mysql works in applets and all classloaders. Thanks to Joe Ennis <jce@mail.boone.com> for pointing out the problem and working on a fix with me.
Fixed DatabaseMetadata problems in getColumns() and bug in switch statement in the Field constructor. Thanks to Costin Manolache <costin@tdiinc.com> for pointing these out.
Incorporated efficiency changes from Richard Swift
<Richard.Swift@kanatek.ca> in
MysqlIO.java and
ResultSet.java:
We're now 15% faster than gwe's driver.
Started working on DatabaseMetaData.
The following methods are implemented:
getTables()
getTableTypes()
getColumns()
getCatalogs()
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