Bug 123219 Export data in attached file which has a table covers multiple page will throw exception.
Description: Export data in attached file which has a table covers multiple page will throw exception. Steps to reproduce: 1. Preview attached design file in viewer. 2. Select the table and click Export Data Expected result: No errors. Actual result: Exception Exception in: ReportEngineService.getMetaData( )
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/DataExtractionTask.java
else
			{
				metaData = new ResultMetaData( null,
						selectedColumns );
				resultMetaList.add( metaData );
			}
		}
		return resultMetaList;
	}
	
	public List getResultSetList( ) throws EngineException
	{	
		if (resultMetaList == null) 
		{
			prepareMetaData( );
			resultMetaList = new ArrayList();
			String dispName = null;
			if( instanceId != null )
			{
				ReportItemDesign reportItem = (ReportItemDesign)report.getReportItemByID( 
						instanceId.getComponentID( ) );
				IBaseQueryDefinition query = reportItem.getQuery( );
				dispName = (String)mapQueryToDispName.get( query ); 
				
				addToResultSetList( query, dispName );
			}
			else
			{
				Set keySet = mapQueryToDispName.keySet( );
				Iterator keyIter = keySet.iterator( );