Re: more select-for-update questions - Mailing list pgsql-general

From Alvaro Herrera
Subject Re: more select-for-update questions
Date
Msg-id 20070815005157.GW9206@alvh.no-ip.org
Whole thread Raw
In response to more select-for-update questions  ("Ed L." <pgsql@bluepolka.net>)
Responses Re: more select-for-update questions  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
Ed L. wrote:
> I ran a simple select-for-update test on 8.1.2 and was curious as
> to why the semantics are what they are.  Specifically, when you
> have multiple select-for-update-limit queries on the same rows,
> why are rows selected by the blocked query before knowing if
> some of those rows will be removed/eliminated by a preceding
> select-for-update-limit?

This is how it is just because of "historical reasons", i.e. it's a
known misfeature that no one has bothered to fix.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

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