SQL statement batching can improve the performance of your
application server. Java™ Persistence
API (JPA) for WebSphere® Application Server uses the Java Database Connectivity (JDBC) addBatch and
executeBatch APIs to batch statements.
About this task
By default, statement batching is enabled for DB2® and
Oracle databases. To enable SQL statement batching and to set the
batch limit for JPA applications, you need to configure the persistence.xml file.
The following steps review how to enable and disable statement batching,
as well as set the batch limit:
Procedure
- Define the UpdateManager property in the persistence.xml file.
For example:
<property name="openjpa.jdbc.UpdateManager"
value="com.ibm.ws.persistence.jdbc.kernel.OperationOrderUpdateManager(batchLimit=100)"/>
Note: The example shows that the SQL statement batch limit is
set to 100.
Remember: If you are using
a DB2 or an Oracle database, by default the SQL
statement batching is enabled and set to batchLimit=100.
However, if you are using DB2 or Oracle, you are not required
to specify this property in the persistence.xml file.
- If you need to disable SQL statement batching, set the
batchLimit value to 0 (zero) or remove the property.
However, if you are using a DB2 or
an Oracle database, you must specify the DBDictionary property, database,
and set the defaultBatchLimit to 0 (zero). For
example:
<property name="openjpa.jdbc.DBDictionary" value="db2(defaultBatchLimit=0)"/>
Results
You have now updated the persistence.xml file to
enable or disable statement batching and set the batch limit.