| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Alvaro Herrera <alvherre(at)commandprompt(dot)com> |
| Cc: | Gregory Stark <gsstark(at)mit(dot)edu>, Luke Lonergan <llonergan(at)greenplum(dot)com>, Chad Wagner <chad(dot)wagner(at)gmail(dot)com>, Simon Riggs <simon(at)2ndquadrant(dot)com>, Igor Lobanov <ilobanov(at)swsoft(dot)com>, Richard Huxton <dev(at)archonet(dot)com>, pgsql-performance(at)postgresql(dot)org |
| Subject: | Re: Querying distinct values from a large table |
| Date: | 2007-01-31 05:55:19 |
| Message-ID: | 16278.1170222919@sss.pgh.pa.us |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-performance |
Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> Gregory Stark wrote:
>> (Incidentally I'm not sure where 2-5x comes from. It's entirely dependant on
>> your data distribution. It's not hard to come up with distributions where it's
>> 1000x as fast and others where there's no speed difference.)
> So the figure is really "1-1000x"? I bet this one is more impressive in
> PHB terms.
Luke has a bad habit of quoting numbers that are obviously derived from
narrow benchmarking scenarios as Universal Truths, rather than providing
the context they were derived in. I wish he'd stop doing that...
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Luke Lonergan | 2007-01-31 06:58:53 | Re: Querying distinct values from a large table |
| Previous Message | Luke Lonergan | 2007-01-30 23:17:48 | Re: Querying distinct values from a large table |