Bug 176107 row.__rownum cannot be directly used as group key
Create a table that bind it to a data set. Insert a group. For the Group On field, click on the "..." button to edit the expression, and select from "Availble Column Bindings" | "Table" | "RowNum". This creates a Group On Expression "row.__rownum". The resulting report design cannot be run. It produces error: Column binding "row.__rownum" does not exist. To workaround this, one must create another binding on the table and set its expression to "row.__rownum", then use the new binding as group key. This should not have been necessary. The "__rownum" binding should be implicitly available in all contexts that have a data set. E.g., it should be usable directly as group key, sort key, and in conditional format expressions, etc. Attached is a sample report that produces the error.
data/org.eclipse.birt.data.tests/test/org/eclipse/birt/data/engine/binding/GroupOnRowTest.java
bindingNameRow[2] = "ROW_AMOUT1";
		bindingNameRow[3] = "ROW_AMOUT2";
		IBaseExpression[] bindingExprRow = new IBaseExpression[4];
		bindingExprRow[0] = new ScriptExpression( "dataSetRow.DATE_FOR_GROUP" );
		bindingExprRow[1] = new ScriptExpression( "dataSetRow.ID" );
		bindingExprRow[2] = new ScriptExpression( "dataSetRow.AMOUNT1" );
		bindingExprRow[3] = new ScriptExpression( "dataSetRow.AMOUNT2" );
		String[] columnStr = new String[]{
				"date_for_group", "id", "amount1", "amount2"
		};
		QueryDefinition qd = this.createQuery( bindingNameGroup,
				bindingExprGroup,
				groupDefn,
				null,
				null,
				null,
				null,
				null,
				null,
				bindingNameRow,
				bindingExprRow );
		String outputStr = getOutputStrForGroupTest( 30,
				qd,
				groupDefn.length,
				bindingNameRow,
				columnStr );
		testPrint( outputStr );
		this.checkOutputFile( );
	}