MySQL Connector/J 5.1.13がリリースされました


バージョン5.1版でのメンテナンスリリースであるMySQL Connector/J 5.1.13が リリースされました。Connector/Jは、MySQL用のタイプ4のpure-Java JDBCドライバです。









以下は、Connector/J 5.13.の変更情報です。

   - Fixed Bug#51266 - jdbc:mysql:loadbalance:// would stick to the first host in the list
in some cases, especially exacerbated if the host was down.

- Replaced URLs of the form jdbc:mysql://host-1,host-2 with a composite of a normal
connection and a jdbc:mysql:loadbalance:// connection for more robustness and cleaner

- Fixed BUG#51643 - Connections using jdbc:mysql:loadbalance:// would have statements
(and prepared statements) that did not have their connections changed upon
commit()/rollback(), and thus applications that held statement instances past
commit()/rollback() could have data written to or read from un-intended connections.

- Fixed BUG#51783 - Load-balanced connections could throw a SQLException incorrectly on
commit() or rollback(). This was not caused by failures in commit or rollback, but rather
by the possibility that the newly-selected physical connection was stale. Added logic to
catch and retry if this happens, up to the number of hosts specified for load-balancing.
Also added new property, loadBalanceValidateConnectionOnSwapServer, which controls
whether to explicitly ping the selected host (otherwise, the host is presumed to be up,
and will only be noticed if auto-commit or transaction isolation state needs to be set
and fails).

- Added loadBalancePingTimeout property to allow a specific timeout to be set for each
ping executed against the servers. This ping is executed when the physical connections
are rebalanced (commit/rollback or communication exception), or when a query starting
with (exactly) "/* ping */" is executed. The latter causes each open underlying physical
connection to be pinged.

- Fixed BUG#51776 - Connection.rollback() could swallow exceptions incorrectly.

- Fixed BUG#52231 - Differences in definitions of which SQLExceptions trigger a
failover event could result in failure to try more than a single host in certain

- Fixed BUG#52534 - Performance regression using load-balanced connection.

- More aggressively purge the statement timeout timers after they've been cancelled to
trade time for memory. This purge only happens if statement timeouts are in use.

- Added management of running load-balanced connections. Statistics can be obtained,
and hosts added/dropped via com.mysql.jdbc.ConnectionGroupManager or the JMX
implementation. This functionality is enabled by setting the new parameter
"loadBalanceConnectionGroup" to the name of the logical grouping of connections.

All load-balanced connections sharing the same loadBalanceConnectionGroup value,
regardless of how the application creates them, will be managed together. To enable
JMX-based management, set loadBalanceEnableJMX=true and ensure that remote JMX is
enabled in the JRE (eg, use

- Added loadBalanceExceptionChecker property, which takes a fully-qualified class name
implementing the com.mysql.jdbc.LoadBalancedExceptionChecker interface. This allows
custom evaluation of SQLExceptions thrown to determine whether they should trigger
failover to an alternate host in load-balanced deployments. The default is

- Added two new properties which allow more flexibility in determining which
SQLExceptions should trigger failover in a load-balanced deployment. The new
"loadBalanceSQLStateFailover" property takes a comma-delimited list of SQLState codes
which are compared to the SQLState of the SQLException (matching done with trailing
wildcard), while "loadBalanceSQLExceptionSubclassFailover" takes a comma-delimited list
of fully-qualified class/interface names, against which the SQLException is checked to
determine if it is an instance of any. Matches trigger failover to an alternate host.

- Fixed Bug#51704 - Re-written batched statements don't honor escape processing flag of
their creator.

As well as the following general bug fixes and improvements:

- Fixed BUG#51666 - StatementInterceptors were never "un-safed" after connection
establishment, causing interceptors which returned result sets pre/post execution would
not work.

- Minor fix in previous patch for Bug#51904. Function ConnectionImpl.setCatalog() was
passed quoted argument thus breaking with "...for the right syntax to use near 'test``'"

- Fix for Bug#51912 - Passing NULL as cat. param to getProcedureColumns with

- Fix for Bug#52167 - Can't parse parameter list with special characters inside

- Fix for Bug#51904 - getProcedureColumns() always returns PROCEDURE_CAT result column

- Fix for Bug#51712 - Display Size is always 0 for columns returned by

- Fix for Bug#51908 - db variable might have end up unassigned when calling
getProcedureColumns()/Functions(). This is a followup on code changes made for Bug#51022.

- Fixed Bug#43576 - Sometimes not able to register OUT parameters for

- Fixed Bug#54175 - Driver doesn't support utf8mb4 for servers 5.5.2 and newer. The
driver now auto-detects servers configured with character_set_server=utf8mb4 or treats
the Java encoding "utf-8" passed via "characterEncoding=..." as utf8mb4 in the "SET
NAMES=" calls it makes when establishing the connection.