Bug 191627 [Regression]Exception occurs when first preview the joint dataset[0706]
Description: [Regression]Exception occurs when preview the flatfile and sampledb joint dataset[0706] Build number: 2.2.0.v20070608-0630 Steps to reproduce: 1, New a flatfile dataset 2, New a CUSTOMER dataset 3, Join two datasets with STATE column 4, Preview in dataset Expected result: Preview successfully Actual result: Exception occurs Error log: A BIRT exception occurred. Plug-in Provider:Eclipse.org Plug-in Name:BIRT Data Engine Plug-in ID:org.eclipse.birt.data Version:2.2.0.v20070607-1421 Error Code:data.engine.ColumnBindingReferToInexistColumn Error Message:Column binding "Employee::CUSTOMERNUMBER" has referred to a data set column "Employee::CUSTOMERNUMBER" which is not exist.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedJointDataSourceQuery.java
* @param isLeftDataSet
	 * @param query
	 */
	private void addSortToQuery( IJoinCondition condition,
			boolean isLeftDataSet, IQueryDefinition query )
	{
		IScriptExpression sortExpression;
		if ( isLeftDataSet )
		{
			sortExpression = condition.getLeftExpression( );
		}
		else
		{
			sortExpression = condition.getRightExpression( );
		}
		SortDefinition sort = new SortDefinition( );
		sort.setExpression( sortExpression.getText( ) );
		query.getSorts( ).add( sort );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.data.engine.impl.PreparedDataSourceQuery#newExecutor()
	 */
	protected QueryExecutor newExecutor( )
	{
		return new JointDataSetQueryExecutor( );
	}
	/*
	 * (non-Javadoc)