Re: multiple identical constraints

On Fri, 30 Apr 1999 15:10:58 GMT, dyrdahl_at_my-dejanews.com wrote:

>In other words, they created a column with a not null constraint. However,
>there are actually two not null constraints for the same column. I am
>assuming that this is a bad idea since every update/insert will check the
>same condition twice.

I had this happen once. We used an automated tool (Erwin) to keep several databases in sync, and at one time the tool kept reapplying the same constraints over and over. We had columns with CHECK constraints where the CHECK constraint was repeated.

Dropping the dupes was a real PITA. Took me the better part of a morning to do two databases, and these constraints had become replicated in the Erwin model, so I had to resync that as well.

>Before I go and drop a bunch of these constraints, I wanted to know if anyone
>could see why there would be two and also if it matters which one of the two
>that I drop?

I can't imagine that it would matter which one you dropped, unless you had a constraint naming convention that you are trying to adhere to.

Jonathan Received on Fri Apr 30 1999 - 21:10:59 CDT