OpenJPA executing prepared statement when none exist in the project - openjpa

Question

I have web project in which I am using OpenJAP for database connectivity. I have configured the persistence.xml and I am able to connect to the database and retrieve the data. But in the console output I am seeing this entry
1953 OpenJPA TRACE [main] openjpa.jdbc.SQL - <t 31156635, conn 6888942> executing prepstmnt 9690924
UPDATE student
SET scourse = ?, sname = ?, sroll = ?
WHERE id = ?
[params=?, ?, ?, ?]
In my whole project till now I have not added any prepared statement or any update statement. I want to know why is OpenJPA executing this statement and what would be performance implication when I am fetching big data in the range of millions?

Answer 1

I have added following code to my build.xml file
<!-- ***************************************************************************************************************** -->
<!-- DO NOT DELETE FOLLOWING CODE. THIS IS ADDED FOR ENCHANCING THE CLASSES AT COMPILE TIME. IT IS REQUIRED BY OPENJPA -->
<!-- Define the classpath to include the necessary files. -->
<!-- ex. openjpa jars, persistence.xml, orm.xml, and target classes -->
<path id="jpa.enhancement.classpath">
<!-- Assuming persistence.xml/orm.xml are in WebContent/WEB-INF/classes/META-INF -->
<pathelement location="WebContent/WEB-INF/classes" />
<!-- Location of the .class files -->
<pathelement location="build/classes" />
<!-- Add the openjpa jars -->
<fileset dir=".">
<include name="**/lib/*.jar" />
</fileset>
</path>
<!-- define the openjpac task; this can be done at the top of the -->
<!-- build.xml file, so it will be available for all targets -->
<taskdef name="openjpac" classname="org.apache.openjpa.ant.PCEnhancerTask" classpathref="jpa.enhancement.classpath" />
<!-- invoke enhancer on all .class files below the model directory -->
<openjpac>
<classpath refid="jpa.enhancement.classpath" />
<fileset dir=".">
<include name="**/model/*.class" />
</fileset>
</openjpac>
<echo message="Enhancement complete" />
<!-- ***************************************************************************************************************** -->
On adding this and setting the eclipse to use this build.xml file to create the WAR file. The objects are getting enhanced and I am not getting the "Executing the prepared statement" Trace in my log also it is not executing the extra "Update" statement.