pentaho/pentaho-kettle · error · KettleDatabaseException

Unexpected error inserting row

Error message

Unexpected error inserting row

What it means

The generic catch-all in the batch flush path: any non-SQLException exception thrown during executeBatch()/commit()/clearBatch() is wrapped in a KettleDatabaseException with this message. It signals an unexpected (usually runtime) failure rather than a plain JDBC SQL error.

Solutions

1. Read the cause chain of the KettleDatabaseException to find the underlying runtime error.
2. Update the JDBC driver to a version compatible with the database and Pentaho/Kettle version.
3. Reduce commit/batch size to lower memory pressure.
4. If the connection was closed, check for concurrent use of the same database connection across steps.

Example fix

// before: commit size 100000 causing OOM with huge rows
// after: set 'Commit size' to 1000 in the TableOutput dialog

try {
  insertStatement.executeBatch();
} catch ( KettleDatabaseException e ) {
  Throwable cause = e.getCause();
  log.error( "Unexpected batch failure", cause ); // inspect cause for driver/runtime issue
  data.db.rollback();
}

When it happens

Trigger: A RuntimeException or driver-specific non-SQLException is thrown from insertStatement.executeBatch(), data.db.commit(), or clearBatch() while batch inserting in writeToTable.

Common situations: JDBC driver bugs or driver class version mismatches; connection closed by another thread; OutOfMemoryError handling large batches; misconfigured Kettle database connection object.

Related errors

• Error updating batch
• Errors encountered (first 10): ...
• No generated keys while "return generated keys" is active!
• dbInterface.getUnsupportedTableOutputMessage()
• Error evaluating Internet address value metadata

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/36209cf3f011c9a5. Report an issue: GitHub.

Appendix: source

Thrown at engine/src/main/java/org/pentaho/di/trans/steps/tableoutput/TableOutput.java:295

      if ( data.useSafePoints ) {
        if ( data.releaseSavepoint ) {
          data.db.releaseSavepoint( data.savepoint );
        }
      }

      // Perform a commit if needed
      //

      if ( ( data.commitSize > 0 ) && ( ( commitCounter % data.commitSize ) == 0 ) ) {
        if ( data.db.getUseBatchInsert( data.batchMode ) ) {
          try {
            insertStatement.executeBatch();
            data.db.commit();
            insertStatement.clearBatch();
          } catch ( SQLException ex ) {
            throw Database.createKettleDatabaseBatchException( "Error updating batch", ex );
          } catch ( Exception ex ) {
            throw new KettleDatabaseException( "Unexpected error inserting row", ex );
          }
        } else {
          // insertRow normal commit
          data.db.commit();
        }
        // Clear the batch/commit counter...
        //
        data.commitCounterMap.put( tableName, Integer.valueOf( 0 ) );
        rowIsSafe = true;
      } else {
        rowIsSafe = false;
      }

      // See if we need to get back the keys as well...
      if ( meta.isReturningGeneratedKeys() ) {
        RowMetaAndData extraKeys = data.db.getGeneratedKeys( insertStatement );

        if ( extraKeys.getRowMeta().size() > 0 ) {

View on GitHub (pinned to f3058517a1)