Date: Mon, 20 Sep 2004 16:27:50 -0700 (PDT)
From: Stephan Szabo <sszabo@megazone.bigpanda.com>
To: Jaime Casanova <systemguards@yahoo.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: unique constraints on foreign keys
In-Reply-To: <20040920231852.9042.qmail@web50002.mail.yahoo.com>
Message-ID: <20040920162457.D84638@megazone.bigpanda.com>
References: <20040920231852.9042.qmail@web50002.mail.yahoo.com>
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On Mon, 20 Sep 2004, Jaime Casanova wrote:

>  --- Stephan Szabo <sszabo@megazone.bigpanda.com>
> escribi=F3:
> >
> > On Mon, 20 Sep 2004, Jaime Casanova wrote:
> >
> > > There is a way to not enforce the creation of a
> > > primary or unique index on a referenced table?
> >
> > Not really. It's not the index that's important
> > per-se, it's the uniqueness that is implied.
>
> OK. What about to teach the planner always do a
> seq on that table and do not ask for use the
> index? but not using "set" instructions. can i do
> that?

Not really. Are you worried about the cost of doing the plan analysis for
the index scan or that it might choose to actually use the index?
Theoretically, it's only going to currently plan the fk scan on status
once per connection because that plan should be saved.