Re: FOR KEY LOCK foreign keys

Excerpts from Robert Haas's message of mié ago 03 12:14:15 -0400 2011:
> On Wed, Jul 27, 2011 at 7:16 PM, Alvaro Herrera
> <alvherre@commandprompt.com> wrote:
> > One thing I have not addressed is Noah's idea about creating a new lock
> > mode, KEY UPDATE, that would let us solve the initial problem that this
> > patch set to resolve in the first place.  I am not clear on exactly how
> > that is to be implemented, because currently heap_update and heap_delete
> > do not grab any kind of lock but instead do their own ad-hoc waiting.  I
> > think that might need to be reshuffled a bit, to which I haven't gotten
> > yet, and is a radical enough idea that I would like it to be discussed
> > by the hackers community at large before setting sail on developing it.
> > In the meantime, this patch does improve the current situation quite a
> > lot.
> 
> I haven't looked at the patch yet, but do you have a pointer to Noah's
> proposal?  And/or a description of how it differs from what you
> implemented here?

Yes, see his review email here:
  http://archives.postgresql.org/message-id/20110211071322.GB26971@tornado.leadboat.com

It's long, but search for the part where he talks about "KEY UPDATE".
The way my patch works is explained by Noah there.

-- 
Álvaro Herrera <alvherre@commandprompt.com>
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