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
}
		return rsIDSet.size( );
	}
	/**
	 * 
	 * @param levelDefn
	 * @param query
	 * @return
	 * @throws DataException 
	 */
	private int getSortDirection( DimLevel level, ICubeQueryDefinition query ) throws DataException
	{
		if ( query.getSorts( ) != null && !query.getSorts( ).isEmpty( ) )
		{
			for ( int i = 0; i < query.getSorts( ).size( ); i++ )
			{
				ISortDefinition sortDfn = ( (ISortDefinition) query.getSorts( )
						.get( i ) );
				String expr = sortDfn.getExpression( ).getText( );
			
				DimLevel info = getDimLevel( expr, query.getBindings( ) );
				if ( level.equals( info ) )
				{
					return sortDfn.getSortDirection( );
				}
			}
		}
		return IDimensionSortDefn.SORT_UNDEFINED;
	}