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
while( keyIter.hasNext( ))
				{
					IBaseQueryDefinition query = (IBaseQueryDefinition)keyIter.next( );
					dispName = (String)mapQueryToDispName.get( query );
					addToResultSetList( query, dispName );
				}
			}
		}
		return resultMetaList;
	}
	/*
	 * create IResultSetItem using display name and IResultMetaData 
	 */
	private void addToResultSetList( IBaseQueryDefinition query, 
			String displayName )
	{
		assert query != null;
		assert displayName != null;
		
		ResultMetaData resultMeta = new ResultMetaData(
				getValueExpressions( query ));
		IResultSetItem resultItem = new ResultSetItem(displayName, resultMeta);
		
		resultMetaList.add( resultItem );
	}
	
	public void selectColumns( String[] columnNames )
	{
		selectedColumns = columnNames;
		currentResult = null;