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 disabled, except with 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, SQL statement batching is enabled and set to
batchLimit=100 by default. 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. If, however, you are
using a DB2 or an Oracle database, you need to 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.