Issue

• Two processes are running parallel but one process, with a easy query, wait till the first process is finished.
• The first log message is visible and the second not. Sometimes it takes one minute till the query execute.

log.info("test get start");
Query query = unitLoadService.getEntityManager().createQuery("select p from employee p where p.name = :name");
        query.setParameter("name", name);
        List<Employee> employees = query.getResultList();
log.info("test get finish");

• We don't lock enities. Change to a native query don't help.
• Database is sql server 2012.
• We use option read committed snapshot in the DB.
• We use hibernate

<property name="hibernate.connection.isolation" value="4096" />

• We got the below exception:

Caused by: javax.persistence.OptimisticLockException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect)

Caused by: org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect):

• OptimisticLockException in Hibernate , we are repeatedly getting an javax.persistence.OptimisticLockException while doing an update/delete to tables. We tried enabling the spy option as well as debugged through the code. What I discovered is that it fails at the following point in class in ResultSetReturnImpl-

public int executeUpdate(PreparedStatement statement) {
        try {
            jdbcCoordinator.getTransactionCoordinator().getTransactionContext().startStatementExecution();
            return statement.executeUpdate();
        }
        catch (SQLException e) {
            throw sqlExceptionHelper.convert( e, "could not execute statement" );
        }
        finally {
            jdbcCoordinator.getTransactionCoordinator().getTransactionContext().endStatementExecution();
        }
    }

• The executeUpdate in above case always returns 0 (and no exceptions) even though the same SQL run on SQL Server 2014 directly updates one row. The PreparedStatement implementation is coming from ironjacamar-jdbc-1.0.28.Final-redhat-1.jar.