Bug 202038 errors occurred when preview the attached design file.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/executor/transform/pass/ResultSetProcessUtil.java
List aggrDefns = this.populator.getEventHandler( ).getAggrDefinitions( );
		
		prepareAggregations( aggrDefns );
		
		
		doGroupFiltering( );
		
		doRowSorting( );
		
		
		doGroupSorting( );
		
		clearTemporaryComputedColumns( iccState );
	}
	/**
	 * 
	 * @param aggrDefns
	 * @throws DataException
	 */
	private void prepareAggregations( List aggrDefns ) throws DataException
	{
		boolean needGroupFiltering = this.needDoGroupFiltering( );
		boolean needGroupSorting = this.needDoGroupSorting( );
		
		if ( needPreCalculateForGroupFilterSort( needGroupFiltering,
				needGroupSorting ) )
		{
			if ( !groupingDone )
			{
				PassUtil.pass( this.populator,