Re: Confirmation of bad query plan generated by 7.4 - Mailing list pgsql-performance

From Jim C. Nasby
Subject Re: Confirmation of bad query plan generated by 7.4
Date
Msg-id 20060614135740.GZ34196@pervasive.com
Whole thread Raw
In response to Re: Confirmation of bad query plan generated by 7.4  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
On Tue, Jun 13, 2006 at 09:50:49PM -0400, Tom Lane wrote:
> "Jim C. Nasby" <jnasby@pervasive.com> writes:
> > On Tue, Jun 13, 2006 at 06:04:42PM -0400, Tom Lane wrote:
> >> It'd depend on the context, possibly, but it's easy to show that the
> >> current planner does fold "now() - interval_constant" when making
> >> estimates.  Simple example:
>
> > Turns out the difference is between feeding a date vs a timestamp into the
> > query... I would have thought that since date is a date that the WHERE clause
> > would be casted to a date if it was a timestamptz, but I guess not...
>
> Hmm ... worksforme.  Could you provide a complete test case?

I can't provide the data I used for that, but I'll try and come up with
something else.
--
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461

pgsql-performance by date:

Previous
From: Sven Geisler
Date:
Subject: Re: how to partition disks
Next
From: "Dave Dutcher"
Date:
Subject: Re: OT - select + must have from - sql standard syntax?