PureQuery provides heterogeneous batching which performs
better than homogeneous batching in JDBC. Applications benefit from
heterogeneous batching if updates in a transaction involve many entity
types and those entities do not have DB-generated keys. To use pureQuery
the JDBC driver must specify the
db2jcc.jar file (pureQuery
does not work with the Informix legacy
JDBC driver,
ifxjdbc.jar file) and in the
persistence.xml file
that is included in the application Java archive
(JAR) file must specify the following:
<property name="pdqProperties" value="dynamic"/>
Important:
- The JDBC provider configuration must include the JAR file for
the IBM Optim pureQuery Runtime environment. This JAR file is in addition
to the JDBC driver JAR file. For more information, see the documentation
about installing IBM Optim pureQuery Runtime.
- If this is an XA data source, define a new custom property on
the data source where property_name = downgradeHoldCursorsUnderXa and
boolean value = true.