Re: Optimizer generates bad plans.

Maybe not nice, but there's only 32 (64 now?) of them...

JOIN pg_attribute WHERE attnum IN (conkeys[1], conkeys[2], conkeys[3],
..., conkeys[32])

Great fun...

On Thu, 2002-09-19 at 18:31, Kris Jurka wrote:
>
> Well I was really hoping pg_constraint would solve all my problems, but
> since contrib/array is not installed by default the conkeys and confkeys
> columns aren't terribly useful because they can't be joined to
> pg_attribute.
>
> Also there is not a column to tell you the unique constraint that
> supports a given foreign key constraint.
>
> See my post to bugs:
>
> http://fts.postgresql.org/db/mw/msg.html?mid=1074855
>
> Kris Jurka
>
>
> On Thu, 19 Sep 2002, Bruce Momjian wrote:
>
> >
> > Congratulations. That is the largest plan I have ever seen. ;-)
> >
> > ---------------------------------------------------------------------------
> >
> > Kris Jurka wrote:
> > > While adding schema support to the JDBC Driver, I came across a query
> > > which occasionally generates some spectacularly bad plans. I have
> > > attached the query and explain analyze outputs against today's cvs head
> > > for queries that take between 9 and 845941 msec. In the JDBC Driver I
> > > will specify a reasonable join order using explicit JOINs, but I thought
> > > someone might be interested in a test case for the optimizer.
> >
> > --
> > Bruce Momjian | http://candle.pha.pa.us
> > pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
> > + If your life is a hard drive, | 13 Roberts Road
> > + Christ can be your backup. | Newtown Square, Pennsylvania 19073
> >
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--
Rod Taylor