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One user reported problems with the JDBC driver 10.0.2.4 and recommended to stay on version 10.0.2.3 or 10.0.2.2. Unfortuneatly there are concurring issues with the JDBC 10.2.0.4 driver against the JDBC 10.2.0.2 driver that is actually shipped with PDI.
Please see http://jira.pentaho.com/browse/PDI-1205 about the backdraw using JDBC 10.2.0.4 driver (issues with batch commits) and http://jira.pentaho.com/browse/PDI-3964 about the backdraw using JDBC 10.2.0.2 driver (loosing precision in certain circumstances).
In gereral we recommend to use the JDBC driver that is suitable for your database version. Please replace the JDBC driver in your distribution folder under libext/JDBC. JDBC drivers are downloadable from http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/index.html
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