D.5. MySQL Connector/J Change History

Fixed can't use XAConnection for local transactions when no global transaction is in progress. (fixes Bug#17401)

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" server variable to the character set that is used for error messages. (Fixes Bug#18086)

Fixed ConnectionProperties (and thus some subclasses) are not serializable, even though some J2EE containers expect them to be. (Fixes Bug#19169)

Fixed MysqlValidConnectionChecker for JBoss doesn't work with MySQLXADataSources. (Fixes Bug#20242)

Better caching of character set converters (per-connection) to remove a bottleneck for multibyte character sets.

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 allows 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).

MysqlXaConnection.recover(int flags) now allows 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.

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.

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.

Attempt detection of the MySQL type BINARY (it's an alias, so this isn't always reliable), and use the java.sql.Types.BINARY type mapping for it.

Moved -bin-g.jar file into separate debug subdirectory to avoid confusion.

Don't allow .setAutoCommit(true), or .commit() or .rollback() on an XA-managed connection as per the JDBC specification.

If the connection useTimezone is set to true, then also respect time zone conversions in escape-processed string literals (for example, "{ts ...}" and "{t ...}").

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's 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.

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).

Added unit tests for XADatasource, as well as friendlier exceptions for XA failures compared to the "stock" XAException (which has no messages).

Idle timeouts cause XAConnections to whine about rolling themselves back. (Bug #14729)

Added support for Connector/MXJ integration via url subprotocol jdbc:mysql:mxj://....

Moved all SQLException constructor usage to a factory in SQLError (ground-work for JDBC-4.0 SQLState-based exception classes).

Removed Java5-specific calls to BigDecimal constructor (when result set value is '', (int)0 was being used as an argument indirectly via method return value. This signature doesn't exist prior to Java5.)

Added service-provider entry to META-INF/services/java.sql.Driver for JDBC-4.0 support.

Return "[VAR]BINARY" for RSMD.getColumnTypeName() when that is actually the type, and it can be distinguished (MySQL-4.1 and newer).

When fix for Bug #14562 was merged from 3.1.12, added functionality for CallableStatement's parameter metadata to return correct information for .getParameterClassName().

Fuller synchronization of Connection to avoid deadlocks when using multithreaded frameworks that multithread a single connection (usually not recommended, but the JDBC spec allows it anyways), part of fix to Bug #14972).

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.

Fixed updatable result set throws ClassCastException when there is row data and moveToInsertRow() is called. (Fixes Bug#20479)

Fixed Updatable result set that contains a BIT column fails when server-side prepared statements are used. (Fixes Bug#20485)

Fixed memory leak with profileSQL=true. (Fixes Bug#16987)

- - Connection fails to localhost when using timeout and IPv6 is configured. (Fixes Bug#19726)

Fixed NullPointerException in MysqlDataSourceFactory due to Reference containing RefAddrs with null content. (Fixes Bug#16791)

Fixed ResultSet.getShort() for UNSIGNED TINYINT returns incorrect values when using server-side prepared statements. (Fixes Bug#20306)

Fixed can't pool server-side prepared statements, exception raised when re-using them. (Fixes Bug#20687 -

INOUT parameter does not store IN value. (Bug #15464)

Exception thrown for new decimal type when using updatable result sets. (Bug #14609)

No "dos" character set in MySQL > 4.1.0. (Bug #15544)

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)

ResultSet.getShort() for UNSIGNED TINYINT returned wrong values. (Bug #11874)

lib-nodist directory missing from package breaks out-of-box build. (Bug #15676)

DBMD.getColumns() returns wrong type for BIT. (Bug #15854)

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)

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)

Fixed Statement.getGeneratedKeys() throws NullPointerException when no query has been processed. (Bug #17099)

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 presense of log4j, too many different incompatible versions out there in the wild to do this reliably. (Bug #13469)

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.

Added support for Apache Commons logging, use "com.mysql.jdbc.log.CommonsLogger" as the value for the "logger" configuration property.

LogFactory now prepends "com.mysql.jdbc.log" to log class name if it can't be found as-specified. This allows you to use "short names" for the built-in log factories, for example "logger=CommonsLogger" instead of "logger=com.mysql.jdbc.log.CommonsLogger".

Fixed issue with ReplicationConnection incorrectly copying state, doesn't transfer connection context correctly when transitioning between the same read-only states. (Bug #15570)

Fixed issue where server-side prepared statements don't cause truncation exceptions to be thrown when truncation happens. (Bug #18041)

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.

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.

Added additional accessor and mutator methods on ConnectionProperties so that DataSource users can use same naming as regular URL properties.

Fixed data truncation and getWarnings() only returns last warning in set. (Bug #18740)

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. Fixes Bug #18496 for BigDecimals.

Fixed aliased column names where length of name > 251 are corrupted. (Bug #18554)

Fixed ResultSet.wasNull() not always reset correctly for booleans when done via conversion for server-side prepared statements. (Bug #17450)

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.

Driver now aware of fix for BIT type metadata that went into MySQL-5.0.21 for server not reporting length consistently (Bug #13601).

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 client-side prepared statement bug with embedded ? characters inside quoted identifiers (it was recognized as a placeholder, when it was not).

Don't allow 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.

Java type conversion may be incorrect for MEDIUMINT. (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).

Fixed DatabaseMetaData.stores*Identifiers():

DatabaseMetaData.getColumns() doesn't return TABLE_NAME correctly. (Bug #14815)

Escape processor replaces quote character in quoted string with string delimiter. (Bug #14909)

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).

Unable to initialize character set mapping tables (due to J2EE classloader differences). (Bug #14938)

Deadlock while closing server-side prepared statements from multiple threads sharing one connection. (Bug #14972)

logSlowQueries should give better info. (Bug #12230)

Extraneous sleep on autoReconnect. (Bug #13775)

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)

maxQuerySizeToLog is not respected. Added logging of bound values for execute() phase of server-side prepared statements when profileSQL=true as well. (Bug #13048)

Usage advisor complains about unreferenced columns, even though they've been referenced. (Bug #15065)

Don't increase timeout for failover/reconnect. (Bug #6577)

Process escape tokens in Connection.prepareStatement(...). (Bug #15141) You can disable this behavior by setting the JDBC URL configuration property processEscapeCodesForPrepStmts to false.

Reconnect during middle of executeBatch() should not occur if autoReconnect is enabled. (Bug #13255)

Spurious ! on console when character encoding is utf8. (Bug #11629)

Fixed statements generated for testcases missing ; for “plain” statements.

Incorrect generation of testcase scripts for server-side prepared statements. (Bug #11663)

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.

Moved source code to Subversion repository.

Escape tokenizer doesn't respect stacked single quotes for escapes. (Bug #11797)

GEOMETRY type not recognized when using server-side prepared statements.

ReplicationConnection won't switch to slave, throws “Catalog can't be null” exception. (Bug #11879)

Properties shared between master and slave with replication connection. (Bug #12218)

Statement.getWarnings() fails with NPE if statement has been closed. (Bug #10630)

Only get char[] from SQL in PreparedStatement.ParseInfo() when needed.

Geometry types not handled with server-side prepared statements. (Bug #12104)

StringUtils.getBytes() doesn't work when using multi-byte character encodings and a length in characters is specified. (Bug #11614)

Pstmt.setObject(...., Types.BOOLEAN) throws exception. (Bug #11798)

maxPerformance.properties mis-spells “elideSetAutoCommits”. (Bug #11976)

DBMD.storesLower/Mixed/UpperIdentifiers() reports incorrect values for servers deployed on Windows. (Bug #11575)

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)

explainSlowQueries hangs with server-side prepared statements. (Bug #12229)

Escape processor didn't honor strings demarcated with double quotes. (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).

Reworked Field class, *Buffer, and MysqlIO to be aware of field lengths > Integer.MAX_VALUE.

Updated DBMD.supportsCorrelatedQueries() to return true for versions > 4.1, supportsGroupByUnrelated() to return true and getResultSetHoldability() to return HOLD_CURSORS_OVER_COMMIT.

Handling of catalog argument in DatabaseMetaData.getIndexInfo(), which also means changes to the following methods in DatabaseMetaData: (Bug #12541)

The catalog argument in all of these methods now behaves in the following way:

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.

Tokenizer for = in URL properties was causing sessionVariables=.... to be parameterized incorrectly. (Bug #12753)

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.

CallableStatement.clearParameters() now clears resources associated with INOUT/OUTPUT parameters as well as INPUT parameters.

Connection.prepareCall() is database name case-sensitive (on Windows systems). (Bug #12417)

cp1251 incorrectly mapped to win1251 for servers newer than 4.0.x. (Bug #12752)

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.

ResultSetMetaData from Statement.getGeneratedKeys() caused a NullPointerException to be thrown whenever a method that required a connection reference was called. (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.

Fixed NullPointerException when converting catalog parameter in many DatabaseMetaDataMethods to byte[]s (for the result set) when the parameter is null. (null isn't technically allowed by the JDBC specification, but we've historically allowed it).

Backport of VAR[BINARY|CHAR] [BINARY] types detection from 5.0 branch.

Read response in MysqlIO.sendFileToServer(), even if the local file can't be opened, otherwise next query issued will fail, because it's reading the response to the empty LOAD DATA INFILE packet sent to the server.

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 via .getStatement() (the default is false, to be JDBC-compliant and to reduce the chance that code using JDBC leaks Statement instances).

URL configuration parameters don't allow ‘&’ 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). (Bug #13453)

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.

The configuration property sessionVariables now allows you to specify variables that start with the ‘@’ sign.

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)

Fixed connecting without a database specified raised an exception in MysqlIO.changeDatabaseTo().

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.

Overhaul of character set configuration, everything now lives in a properties file.

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.

com.mysql.jdbc.PreparedStatement.ParseInfo does unnecessary call to toCharArray(). (Bug #9064)

Memory leak in ServerPreparedStatement if serverPrepare() fails. (Bug #10144)

Actually write manifest file to correct place so it ends up in the binary jar file.

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.

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)

Double quotes not recognized when parsing client-side prepared statements. (Bug #10155)

Made enableStreamingResults() visible on com.mysql.jdbc.jdbc2.optional.StatementWrapper.

Made ServerPreparedStatement.asSql() work correctly so auto-explain functionality would work with server-side prepared statements.

Made JDBC2-compliant wrappers public in order to allow access to vendor extensions.

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.

DatabaseMetaData.supportsMultipleOpenResults() now returns true. The driver has supported this for some time, DBMD just missed that fact.

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)

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)

The datatype 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.

SQLException is thrown when using property characterSetResults with cp932 or eucjpms. (Bug #10496)

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.

Added support/bug hunting feature that generates .sql test scripts to STDERR when autoGenerateTestcaseScript is set to true.

0-length streams not sent to server when using server-side prepared statements. (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.

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.

Don't send COM_RESET_STMT for each execution of a server-side prepared statement if it isn't required.

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.

VARBINARY data corrupted when using server-side prepared statements and ResultSet.getBytes(). (Bug #11115)

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.

Added the following configuration bundles, use one or many via the useConfigs configuration property:

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.

autoReconnect ping causes exception on connection startup. (Bug #11259)

Connector/J dumping query into SQLException twice. (Bug #11360)

Fixed PreparedStatement.setClob() not accepting null as a parameter.

Production package doesn't include JBoss integration classes. (Bug #11411)

Removed nonsensical “costly type conversion” warnings when using usage advisor.

Fixed DatabaseMetaData.getTables() returning views when they were not asked for as one of the requested table types.

Added support for new precision-math DECIMAL type in MySQL 5.0.3 and up.

Fixed ResultSet.getTime() on a NULL value for server-side prepared statements throws NPE.

Made Connection.ping() a public method.

DATE_FORMAT() queries returned as BLOBs from getObject(). (Bug #8868)

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).

BlobFromLocator now uses correct identifier quoting when generating prepared statements.

Server-side session variables can be preset at connection time by passing them as a comma-delimited list for the connection property sessionVariables.

Fixed regression in ping() for users using autoReconnect=true.

PreparedStatement.addBatch() doesn't work with server-side prepared statements and streaming BINARY data. (Bug #9040)

DBMD.supportsMixedCase*Identifiers() returns wrong value on servers running on case-sensitive filesystems. (Bug #8800)

Cannot use UTF-8 for characterSetResults configuration property. (Bug #9206)

A continuation of Bug #8868, where functions used in queries that should return non-string 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)

DBMD.supportsResultSetConcurrency() not returning true for forward-only/read-only result sets (we obviously support this). (Bug #8792)

DATA_TYPE column from DBMD.getBestRowIdentifier() causes ArrayIndexOutOfBoundsException when accessed (and in fact, didn't return any value). (Bug #8803)

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).

PreparedStatement.getMetaData() inserts blank row in database under certain conditions when not using server-side prepared statements. (Bug #9320)

Connection.canHandleAsPreparedStatement() now makes “best effort” to distinguish LIMIT clauses with placeholders in them from ones without in order to have fewer false positives when generating work-arounds for statements the server cannot currently handle as server-side prepared statements.

Fixed build.xml to not compile log4j logging if log4j not available.

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.

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.

Stored procedures with same name in different databases confuse the driver when it tries to determine parameter counts/types. (Bug #9319)

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.

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.

Statement.getMoreResults() could throw NPE when existing result set was .close()d. (Bug #9704)

The performance metrics feature now gathers information about number of tables referenced in a SELECT.

The logging system is now automatically configured. If the value has been set by the user, via the URL property logger or the system property com.mysql.jdbc.logger, then use that, otherwise, autodetect it using the following steps:

DBMD.getTables() shouldn't return tables if views are asked for, even if the database version doesn't support views. (Bug #9778)

Fixed driver not returning true for -1 when ResultSet.getBoolean() was called on result sets returned from server-side prepared statements.

Added a Manifest.MF file with implementation information to the .jar file.

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.

Should accept null for catalog (meaning use current) in DBMD methods, even though it's 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)

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)

Timestamp key column data needed _binary stripped for UpdatableResultSet.refreshRow(). (Bug #7686)

Timestamps converted incorrectly to strings with server-side prepared statements and updatable result sets. (Bug #7715)

Detect new sql_mode variable in string form (it used to be integer) and adjust quoting method for strings appropriately.

Added holdResultsOpenOverStatementClose property (default is false), that keeps result sets open over statement.close() or new execution on same statement (suggested by Kevin Burton).

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.

Fixed duplicated code in configureClientCharset() that prevented useOldUTF8Behavior=true from working properly.

Removed dontUnpackBinaryResults functionality, the driver now always stores results from server-side prepared statements as is from the server and unpacks them on demand.

Emulated locators corrupt binary data when using server-side prepared statements. (Bug #8096)

Fixed synchronization issue with ServerPreparedStatement.serverPrepare() that could cause deadlocks/crashes if connection was shared between threads.

By default, the driver now scans SQL you are preparing via 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)

Remove _binary introducer from parameters used as in/out parameters in CallableStatement.

Always return byte[]s for output parameters registered as *BINARY.

Send correct value for “boolean” true to server for PreparedStatement.setObject(n, "true", Types.BIT).

Fixed bug with Connection not caching statements from prepareStatement() when the statement wasn't a server-side prepared statement.

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).

Added dontTrackOpenResources option (default is false, to be JDBC compliant), which helps with memory use for non-well-behaved apps (that is, applications that don't close Statement objects when they should).

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)

Fixed NPE in ResultSet.realClose() when using usage advisor and result set was already closed.

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.

ResultSet.getBigDecimal() throws exception when rounding would need to occur to set scale. The driver now chooses a rounding mode of “half up” if non-rounding BigDecimal.setScale() fails. (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.

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.

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.

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 n on the end of it.