I would like to find out if the a part exists when it is entered. I have a table called Snum and a View called validpart. When an insert is done on the PartNumber field in the Snum table I want it to see if that part exists in the validpart view. If it does great- if not then error rollback etc... It's my understand that you cannot create relationship with a view so my only options are either a trigger or constraint.