>>Tamar
>
>Thank you very much for the detailed explanation. And for the links to your articles. Your descriptions really helps to understand. I already printed one of your articles on Handling Hierarchical Data.
>As to CTE, I don't know if this will work on my PC since I still use SQL Server 2008 Developers Edition. I may try a simple example just to make sure the CTE works on this version of SQL Server and I can test a different approach.
>Again, thank you!

CTEs work from SQL Server 2005.