Bug 182895 Support sort on Level attribute.
Currently in OLAP engine we only support sort on level key value. We should go ahead to support sort on level attribute value.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/olap/query/view/QueryExecutor.java
sortType[i] = getSortDirection( levelsForFilter[i], query );
			}
			aggregations[aggrIndex] = new AggregationDefinition( levelsForFilter,
					sortType,
					null );
			aggrIndex++;
		}
		if ( calculatedMember != null && calculatedMember.length > 0 )
		{
			List list;
			Set rsIDSet = new HashSet( );
			for ( int i = 0; i < calculatedMember.length; i++ )
			{
				if ( rsIDSet.contains( new Integer( calculatedMember[i].getRsID( ) ) ) )
					continue;
				list = getCalculatedMemberWithSameRSId( calculatedMember, i );
				AggregationFunctionDefinition[] funcitons = new AggregationFunctionDefinition[list.size( )];
				for ( int index = 0; index < list.size( ); index++ )
				{
					String[] dimInfo = ( (CalculatedMember) list.get( index ) ).getFirstArgumentInfo( );
					String dimName = null;
					String levelName = null;
					String attributeName = null;
					DimLevel dimLevel = null;
					if ( dimInfo != null && dimInfo.length == 3 )
					{
						dimName = ( (CalculatedMember) list.get( index ) ).getFirstArgumentInfo( )[0];
						levelName = ( (CalculatedMember) list.get( index ) ).getFirstArgumentInfo( )[1];
						attributeName = ( (CalculatedMember) list.get( index ) ).getFirstArgumentInfo( )[2];
						dimLevel = new DimLevel( dimName, levelName );