Re: deferred foreign keys - Mailing list pgsql-performance

From Vivek Khera
Subject Re: deferred foreign keys
Date
Msg-id A4624C54-3FB1-11D8-A8A5-000A9578CFCC@kcilink.com
Whole thread Raw
In response to Re: deferred foreign keys  (Stephan Szabo <sszabo@megazone.bigpanda.com>)
Responses Re: deferred foreign keys
List pgsql-performance
On Jan 5, 2004, at 1:57 PM, Stephan Szabo wrote:

> But, if he's updating the fk table but not the keyed column, it should
> no
> longer be doing the check and grabbing the locks.  If he's seeing it
> grab
> the row locks still a full test case would be handy because it'd
> probably
> mean we missed something.
>

I'm not *sure* it is taking any locks.  The transactions appear to be
running lock step (operating on different parts of the same pair of
tables) and I was going to see if deferring the locks made the
difference.  It is my feeling now that it will not.  However, if there
is a way to detect if locks are being taken, I'll do that.  I'd like to
avoid dropping and recreating the foreign keys if I can since it takes
up some bit of time on the table with 20+ million rows.

Vivek Khera, Ph.D.
+1-301-869-4449 x806


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