Description Hans Harz 2010-09-03 08:42:48 EDT

Build Identifier: 2.1.1.v20100817-r8050

Investigation shows that there seems to be an inconsistency in how EclipseLink in ParameterizedSQLBatchWritingMechanism computes the number of entities that should be affected by a "batch" query and the number that is returned by the Oracle specific implementation of DatabasePlatform.executeBatch()

Furthermore we notice that of all DatabasePlatform implementations Oracle10Platform is the only one that overrides canBatchWriteWithOptimisticLocking() to return true.

Workaround:
- Either: override Oracle10Platform.canBatchWriteWithOptimisticLocking() to return always false
- Or: (less invasive, but switching off all batch writing) set eclipselink.jdbc.batch-writing to NONE

Notes:
- Our code works fine with many other database backends, e.g. H2, DB2, Postgresql, MS SQL


Reproducible: Always

Steps to Reproduce:
Steps to reproduce: 
- Use Oracle 10 or 11 as backend with the Oracle10Platform
- OptimisticLocking should be active (by default?)
- eclipselink.jdbc.batch-writing is set to JDBC or Oracle-JDBC
- Execute a JPA Query that deletes multiple rows, e.g.
  DELETE FROM MyEntityClass AS c WHERE c.id IN (1, 2, 3, ...)
  with the Query.executeUpdate() method


Result:
- OptimisticLockException is thrown in ParameterizedSQLBatchWritingMechanism.executeBatchedStatements()
with exception description: "One or more objects cannot be updated because it has changed or been deleted since it was last read"