Re: Pulling data from a constraint def

On Thu, May 13, 2010 at 12:33:08AM -0400, Tom Lane wrote:
> Josh Kupershmidt <schmiddy(at)gmail(dot)com> writes:
> > On Wed, May 12, 2010 at 12:58 AM, David Fetter <david(at)fetter(dot)org> wrote:
> >> If you've measured a performance issue for a table that tiny, it's a
> >> bug that needs fixing in PostgreSQL. What measurements have you done
> >> so far?
>
> > Just for fun, I tried it out myself. Here are the times I got on my
> > modest laptop:
>
> > CHECK constraint:
> > * 500k INSERTs: 3.8 seconds
> > * 500k UPDATEs: 6.0 seconds
>
> > Foreign Key:
> > * 500k INSERTs: 18.7 seconds
> > * 500k UPDATEs: 21.2 seconds
>
> I'm surprised no one has yet suggested an ENUM type.

I didn't suggest it because I didn't know about it, but because I've
found ENUM to be a trap for the unwary.

Very seldom are people absolutely certain that they'll have one
particular list of things forever. The list may grow or shrink, or
the order may change, and in those cases where the list changes
somehow, ENUM causes more problems than it solves.

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
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