Skip site navigation (1) Skip section navigation (2)

Re: improving foreign key locks

From: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
To: Florian Pflug <fgp(at)phlo(dot)org>
Cc: Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: improving foreign key locks
Date: 2010-11-29 21:12:56
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-hackers
Excerpts from Alvaro Herrera's message of lun nov 29 18:00:55 -0300 2010:

> This would require some additions in ri_FetchConstraintInfo().  Right
> now it does a single syscache lookup and then extracts a bunch of
> attributes from there.  If we're going to implement as you suggest, we'd
> have to:
> 1. add a relcache lookup in there, and extract column names involved in
> the FK.
> 2. store those column names in RI_ConstraintInfo; currently it's about
> 68 bytes, it'd grow to ~2116 bytes (current size plus RI_MAX_NUMKEYS * NAMEDATALEN).
> Additionally, we'd have to expend some more cycles at the parse analysis
> phase (of the "FOR SHARE OF x.col1, x.col2" query) to verify that those
> columns belong into some non-partial unique index.

Hmm, actually there's already a relcache lookup when we execute whatever
action the FK needs to execute, so maybe we don't need to do any of

Álvaro Herrera <alvherre(at)commandprompt(dot)com>
The PostgreSQL Company - Command Prompt, Inc.
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

In response to


pgsql-hackers by date

Next:From: David FetterDate: 2010-11-29 21:14:54
Subject: Re: Re: [COMMITTERS] pgsql: Remove outdated comments from the regression test files.
Previous:From: Alvaro HerreraDate: 2010-11-29 21:00:55
Subject: Re: improving foreign key locks

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group