Re: Foreign Keys Constraints, perforamance analysis

From: Daniel Åkerud <zilch(at)home(dot)se>
To: <pgsql-general(at)postgresql(dot)org>
Subject: Re: Foreign Keys Constraints, perforamance analysis
Date: 2001-06-25 16:37:02
Message-ID: 012001c0fd95$107c9b50$c901a8c0@automatic100
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

> > OK, I've been discussing this with a collegue of mine... and I'm
starting to
> > see the light here...
> >
> > I will, first of all, make a new, simpler, 1<->1 realtionship to test FK
> > constraints... no 2<->1<->2 relasionship here...
> >
> > Person -> Item/item_fkc
> >
> > And I will do no bulk-delete. Instead these tests:
> >
> > Fill person. no time measuring.
> > Fill item, no foreign keys constraints, time measuring.
> > Fill item, foreign keys constraints
> > Compare last to measurments. How much do you loose in performance having
the
> > Foreign Key check?
> > For all persons {
> > if (fkc)
> > delete from person where id = $id
> > else
> > delete from person where id = $id; delete from item where
personid=$id
> > }
> > Compare measurements. How much do you loose having the foreign keys
> > constraints delete the item?
> >
> > This, I think, this is a more fair comparison.
> >
> > Can you call the FK itself a foreign key constraint, as it actually is
> > constraining something?
>
> Yeah, that's a more even test. Since it sounds like you're writing
> something on foreign key constraints (presumably about postgres), you
> might want to mention the differences with table clearing deletes
> but point out the foreign key constraints aren't generally used in
> schemas where you're doing that :)
>
> As for naming, I'd think so. It is a constraint, just that
> "foreign key constraint" is much longer to type than FK :)
>

Thanks :)

Daniel Åkerud

In response to

Browse pgsql-general by date

  From Date Subject
Next Message Justin Clift 2001-06-25 16:42:30 Re: Red Hat to support PostgreSQL
Previous Message Daniel Åkerud 2001-06-25 16:34:59 Re: MySQL comparison