> There will be 5 users sharing the table
> I think there will be no risk of a repeated code, will it ?

It does not have anything to do with "repeating". The problem is hitting the "save-button" at the same time. And for that two users would be enough. However with the number of users chances rise.

Everyhing might be OK for the next five years. Suddenly You have a field that should be primary key twice. You will not be able to remember in five Years, how this could possibly happen. If You go for this approach You definitely *do* have a timebomb there.

On the other hand this is a task You might have in almost any table You will ever use (if You use primary keys) and so writing a secure Procedure *once*, will save You a lot of sleepless nights.

You really can take my NewId()-function it might take a few minutes to understand what's going on and to comment out some of the lines that are not needed. Then You're done and never have to think of that problem again.