For anyone who is interested, here is my solution: SELECT Orders.ExampleData FROM OrderSeq AS Orders LEFT JOIN OrderSeq AS Updates ON (Orders.OrderId = Updates.OldOrderId) AND (Updates.[Type] = 'U') where (Updates.RowId IS NULL) I knew it was easy, just couldn't get my head around it this morning. Thanks to everyone who replied.

Thanks, I will give it a go.

Hi Leslie, Thanks again for your comments. I did originally want to use the Visitor pattern but I will extend the application with more elements and I think that is where the Visitor pattern falls down. I did look at another pattern, a quick search on Google tells me it was called Acyclic Visitor, however, it didn't tick all the boxes either. Regards, Adam