On Sat, 8 Jan 2000, Tom Lane wrote:
> The Hermit Hacker <scrappy@hub.org> writes:
> > Forbid merge:
> > Hash Join (cost=9994.31 rows=2740488 width=36)
> > -> Seq Scan on url (cost=3368.58 rows=37866 width=20)
> > -> Hash (cost=3368.58 rows=37866 width=16)
> > -> Seq Scan on url url2 (cost=3368.58 rows=37866 width=16)
>
> > 0.900u 0.217s 0:04.19 26.4% 103+14638k 0+175io 0pf+0w
>
> > Forbid Hash:
> > Merge Join (cost=11188.76 rows=2740488 width=36)
> > -> Index Scan using url_pkey on url url2 (cost=4347.30 rows=37866 width=16)
> > -> Index Scan using url_referrer on url (cost=4342.30 rows=37866 width=20)
>
> > 0.897u 0.210s 0:03.19 34.4% 106+15120k 0+179io 0pf+0w
>
> Thanks, but I'm confused about what I'm looking at here. Are those
> time outputs for the backend, or for psql?
just from psql ...
> Also, how large are these two tables, and how many rows do you actually
> get from the query?
pgsql> grep http query.out | wc -l 37825
Can't give you a count on the tables though, since I've since had to
rebuiild them :( Or, rather, the two tables are the same table...
