From: | "Dan Langille" <dan(at)langille(dot)org> |
---|---|
To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | pgsql-sql(at)postgresql(dot)org |
Subject: | Re: subselect instead of a view... |
Date: | 2002-11-26 15:17:26 |
Message-ID: | 3DE34A36.29690.D7D88D0C@localhost |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-sql |
On 26 Nov 2002 at 0:29, Tom Lane wrote:
> "Dan Langille" <dan(at)langille(dot)org> writes:
> > SELECT E.name, EP.pathname, E.id, EP2.pathname, CL.id
> > ...
> > and EP2.pathname like EP.pathname || '/%'
>
> > I am still suspicous of that like. It seems to be the performance
> > killer here. There is an index which can be used:
>
> It won't be, though. The LIKE-to-indexscan transformation happens at
> plan time, and that means it can only happen if the pattern is a
> constant. Which it surely will not be in your example.
Thanks. I'll see if I can come up with something else to do this.
--
Dan Langille : http://www.langille.org/
From | Date | Subject | |
---|---|---|---|
Next Message | Richard Huxton | 2002-11-26 15:24:05 | Re: Two TIMESTAMPs in one pl/sql function |
Previous Message | Henshall, Stuart - Design & Print | 2002-11-26 15:12:02 | Re: How does postgres handle non literal string values |