Kevin,

Have you tried to use the parent or child syntax in your filter expression? I know it works for computed columns when there is a relation between tables but I have never tried it for filtering.

example:
child(relationname).mydescript='something'

>RowFilter is a property of the datatable and select() is also a method of the datatable. So they'll only operate on columns in that specific table.
>
>If you try to issue a myTable.Select( " myothertable.mydescript = 'something' "), you'll likely get some type of error that "myothertable.mydescript" isn't part of mytable, even if a relation has been defined.
>
>I just did a test as a sanity check, and it errored out, the way I would have expected. (Unless someone is aware of some other syntax or capability...)
>