Re: Index on timestamp field, and now()

On Tuesday 12 February 2002 21:34, Tom Lane wrote:
> Denis Perchine <dyp(at)perchine(dot)com> writes:
> > webmailstation=> explain select * from queue where send_date > timestamp
> > 'now';
> >
> > But I use a comparison with now() + '20 years'::interval, not with
> > now()...
>
> That's not the example you quoted. More to the point, if you write it
> that way then it isn't a constant, at least not in 7.2's limited
> understanding of what constant values are. You could work around that
> with a custom function marked isCachable; see the archives.

Oups. Sorry my mistake. But 7.2's limited understanding is enough to do
constant propagation as far as I can see. :-)))

webmailstation=> explain select * from queue where send_date > timestamp
'now' + '20 years'::interval;
NOTICE: QUERY PLAN:

Index Scan using queue_senddate_key on queue (cost=0.00..30.55 rows=8
width=192)

EXPLAIN

Thanks for the hint.

--
Denis