Bug 182680 Use feature of new Aggregation framework of Data Engine.
DataEngine will implement new aggregation framework in 2.2.0RC0. After the implementation is finished Engine should go ahead to use new column bindings in definition of map/highlight.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/DataExtractionTask.java
executionContext.setPresentationMode( true );
	}
	/*
	 * prepare the meta data of DataExtractionTask.
	 */
	private void prepareMetaData( )
	{
		if ( isMetaDataPrepared == true )
			return;
		IDataEngine dataEngine = executionContext.getDataEngine( );
		dataEngine.prepare( report, executionContext.getAppContext( ) );
		
		HashMap queryIds = report.getQueryIDs( );
		HashMap query2itemMapping = report.getReportItemToQueryMap( );
		Iterator iter = queryIds.entrySet( ).iterator( );
		while ( iter.hasNext( ) )
		{
			Map.Entry entry = (Map.Entry) iter.next( );
			IBaseQueryDefinition baseQuery = (IBaseQueryDefinition) entry.getKey( );
			if ( baseQuery instanceof IQueryDefinition )
			{
				IQueryDefinition query = (IQueryDefinition) baseQuery;
				String queryId = (String) entry.getValue( );
				ReportItemDesign item = (ReportItemDesign) query2itemMapping.get( query );
				String queryName = item.getName( );
				if ( queryName == null )
				{
					queryName = "ELEMENT_" + item.getID( );
				}
				queryId2NameMapping.put( queryId, queryName );