| From: | Richard Neill <rn214(at)cam(dot)ac(dot)uk> |
|---|---|
| To: | Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov> |
| Cc: | "<Richard Neill" <rn214(at)cam(dot)ac(dot)uk>, Matthew Wakeling <matthew(at)flymine(dot)org>, jmpoure(at)free(dot)fr, PostgreSQL Performance <pgsql-performance(at)postgresql(dot)org>, Craig Ringer <craig(at)postnewspapers(dot)com(dot)au>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Subject: | Re: Order by (for 15 rows) adds 30 seconds to query time |
| Date: | 2009-12-02 23:04:31 |
| Message-ID: | 4B16F27F.2020005@cam.ac.uk |
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| Lists: | pgsql-performance |
Kevin Grittner wrote:
> Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
>> That does look weird. Do we have a self-contained test case?
Not at the moment. It seems to only occur with relatively complex joins.
>
> Richard, could you capture the schema for the affected tables and
> views with pg_dump -s and also the related rows from pg_statistic?
> (The actual table contents aren't needed to see this issue.)
>
Here are the relevant parts of the schema - I've cut this out of the
source-tree rather than pg_dump, since it seems more readable.
Regarding pg_statistic, I don't understand how to find the relevant
rows - what am I looking for? (the pg_statistic table is 247M in size).
Thanks for your help,
Richard
| Attachment | Content-Type | Size |
|---|---|---|
| schema.sql | text/x-sql | 5.9 KB |
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