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
private boolean needDoGroupFiltering( )
	{
		for ( int i = 0; i < this.populator.getQuery( ).getGrouping( ).length; i++ )
		{
			List groupFilters = this.populator.getQuery( ).getGrouping( )[i].getFilters( );
			if( groupFilters != null && groupFilters.size( ) > 0 )
				return true;
		}
		return false;
	}
	
	/**
	 * Indicate whether need to do group sorting.
	 * @return
	 */
	private boolean needDoGroupSorting( )
	{
		for ( int i = 0; i < this.populator.getQuery( ).getGrouping( ).length; i++ )
		{
			List groupFilters = this.populator.getQuery( ).getGrouping( )[i].getSorts( );
			if( groupFilters != null && groupFilters.size( ) > 0 )
				return true;
		}
		return false;
	}
	
	/**
	 * 
	 * @param aggCCList
	 * @throws DataException