| From: | Alvaro Herrera <alvherre(at)commandprompt(dot)com> |
|---|---|
| To: | Josh Harrison <joshques(at)gmail(dot)com> |
| Cc: | "A(dot) Kretschmer" <andreas(dot)kretschmer(at)schollglas(dot)com>, pgsql-general(at)postgresql(dot)org |
| Subject: | Re: quick question abt pg_dump and restore |
| Date: | 2008-01-09 15:27:50 |
| Message-ID: | 20080109152750.GD4651@alvh.no-ip.org |
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| Thread: | |
| Lists: | pgsql-general |
Josh Harrison escribió:
> Another quick question...When you issue a query like this
> select * from dummy limit 10
> What 10 rows are fetched? like first 10 or last 10 or the first 10 from
> first block or.... ?
Any 10. (First 10 in the physical table _if_ a seqscan is used).
> And this query always returns the same 10 rows (when there are no
> updates/deletes)
Yes, assuming there is no VACUUM or CLUSTER either. And no inserts
either if there is free space on the first pages.
You really shouldn't trust it.
--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.
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