Re: question on index access

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Neil Conway <nconway(at)klamath(dot)dyndns(dot)org>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: question on index access
Date: 2002-03-15 23:23:47
Message-ID: 6281.1016234627@sss.pgh.pa.us
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Neil Conway <nconway(at)klamath(dot)dyndns(dot)org> writes:
> AFAIK, current Postgres behavior when processing SELECT queries is like
> this:
> (1) for each tuple in the result set, try to get an
> AccessShareLock on it

Uh, no. There are no per-tuple locks, other than SELECT FOR UPDATE
which doesn't affect SELECT at all. AccessShareLock is taken on the
entire table, mainly as a means of ensuring the table doesn't disappear
from under us.

regards, tom lane

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