Bug 200516 CachedQueryResults should also implement IQueryService.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/QueryExecutor.java
* @see org.eclipse.birt.data.engine.impl.IQueryExecutor#close()
	 */
	public void close( )
	{
		if ( odiQuery == null )
		{
			
			logger.logp( Level.FINER,
					QueryExecutor.class.getName( ),
					"close",
					"executor closed " );
			return;
		}
		
		try
		{
			dataSet.beforeClose( );
		}
		catch ( DataException e )
		{
			logger.logp( Level.FINE,
					QueryExecutor.class.getName( ),
					"close",
					e.getMessage( ),
					e );
		}
		if ( odiResult != null )
			odiResult.close( );
		odiQuery.close( );
		try