>Had this problem recently though where the user ended up creating an endless loop.
>
>Original setup:
>
>Certas Insurance [Aurora, ON branch], Company_ID = 7204, ParentCoID = 4778 [Desjardin Insurance Co.]
>Certas Insurance [Mississauga, ON branch], Company_ID = 7682, ParentCoID = 7204
>

For structural changes under user control, I always use belt+suspenders approach, first force a backup, then edit after saving either columns or work on temp columns copied on start. User can ALWAYS fall back.

....
>The only way I can think of to cover off all possibilities is to process the tree from the top and see if at any node an endless loop has been set up - a lot of cpu work given that some of the larger insurance companies can have hundreds of branches under them.

Given good indices on small data types this should tax disc more than CPU (unless all data is cached), but that check should be quite fast.

Can you post count() grouped by level ? Or post 2 zip files, with and without errors to play with ?

rgds

thomas