| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | "Thalis A(dot) Kalfigopoulos" <thalis(at)cs(dot)pitt(dot)edu> |
| Cc: | pgsql-general(at)postgresql(dot)org |
| Subject: | Re: INNER JOIN ON vs ','+WHERE |
| Date: | 2001-06-25 17:52:48 |
| Message-ID: | 16712.993491568@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
"Thalis A. Kalfigopoulos" <thalis(at)cs(dot)pitt(dot)edu> writes:
> I noticed that doing a join with the INNER JOIN ON... syntax gives a different execution plan (for complex queries at least) than when using the ',' syntax with the join conditions in the WHERE clause. Actually the latter proved more efficient :-/
> I assume/guess/speculate that the optimizer gets more freedom in the order it'll perform the join when all conditions are just thrown in the WHERE clause whereas the former case forces it to follow the user provided join order?
http://www.ca.postgresql.org/users-lounge/docs/7.1/postgres/explicit-joins.html
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Trond Eivind =?iso-8859-1?q?Glomsr=F8d?= | 2001-06-25 18:08:54 | Re: Red Hat to support PostgreSQL |
| Previous Message | Thalis A. Kalfigopoulos | 2001-06-25 17:38:46 | Re: Red Hat to support PostgreSQL |