Re: Index on timestamp field, and now()

On Tuesday 12 February 2002 20:48, Tom Lane wrote:
> Denis Perchine <dyp(at)perchine(dot)com> writes:
> > webmailstation=> explain select * from queue where send_date > timestamp
> > 'now';
> > NOTICE: QUERY PLAN:
> >
> > Seq Scan on queue (cost=0.00..10114.06 rows=80834 width=190)
> >
> > EXPLAIN
> >
> > queue | send_date | 0 | 8 | -1 |
> >
> >
> >
> >
> >
> >
> > {"2001-12-27 21:58:24-05","2002-02-12 08:48:18.967111-05","2002-02-12
> > 15:14:51.89063-05","2002-02-13 04:06:19.979181-05","2002-02-13
> > 16:20:37.753221-05","2002-02-14 12:03:09.714262-05","2002-02-15
> > 15:15:58.04151-05","2002-02-17 11:06:16.964311-05","2002-02-20
> > 08:40:57.795043-05","2002-03-12 07:25:46-05","2003-10-28 14:58:58-05"}
> >
> > | -0.359735
>
> According to this histogram, 90% of your table has send_date in the
> future. Accordingly, seqscan is the right plan for the above query.

But I use a comparison with now() + '20 years'::interval, not with now()...
And as I have mentioned, there is no any entries more than 20 years in the
feature there.

--
Denis