Re: FOREIGN KEYS vs PERFORMANCE

Jim C. Nasby wrote:
>>1. You have only one application that modifies the data. (Otherwise, you
>>have to duplicate the rules across many applications, leading to a
>>code-maintenance nightmare).
>
> You forgot something:
>
> 1a: You know that there will never, ever, ever, ever, be any other
> application that wants to talk to the database.
>
> I know tons of people that get burned because they go with something
> that's "good enough for now", and then regret that decision for years to
> come.

No, I don't agree with this. Too many people waste time designing for "what if..." scenarios that never happen. You don't want to be dumb and design something that locks out a foreseeable and likely future need, but referential integrity doesn't meet this criterion. There's nothing to keep you from changing from app-managed to database-managed referential integrity if your needs change.

Design for your current requirements.

Let us be of good cheer, remembering that the misfortunes hardest to bear are
those which never happen. - James Russell Lowell (1819-1891)

Therefore do not be anxious about tomorrow, for tomorrow will be anxious for
itself. Let the day's own trouble be sufficient for the day.
- Matthew 6:34

Craig