Home > Archive > PostgreSQL Documentation > July 2005 > ROW SHARE/SELECT ... FOR UPDATE + foreign keys









You are viewing an archived Text-only version of the thread. To view this thread in it's original format and/or if you want to reply to this thread please [click here]

 

Author ROW SHARE/SELECT ... FOR UPDATE + foreign keys
Thomas F. O'Connell

2005-07-21, 8:24 pm

What would people think of adding a note to the ROW SHARE section of
Table-Level Locks remarking on the fact that referential integrity
checks expressed through foreign keys do SELECT ... FOR UPDATES.

http://www.postgresql.org/docs/8.0/static/explicit-
locking.html#LOCKING-TABLES

It was somewhat challenging today to try to track down a pervasive
locking issue related to a table not directly referenced in a stored
procedure but that was referenced by a key in a table that was being
updated.

I'm not sure how this changes with the new shared row locking
implementation in 8.1...

--
Thomas F. O'Connell
Co-Founder, Information Architect
Sitening, LLC

Strategic Open Source: Open Your i™

http://www.sitening.com/
110 30th Avenue North, Suite 6
Nashville, TN 37203-6320
615-260-0005


Bruce Momjian

2005-07-22, 3:26 am

Thomas F. O'Connell wrote:
> What would people think of adding a note to the ROW SHARE section of
> Table-Level Locks remarking on the fact that referential integrity
> checks expressed through foreign keys do SELECT ... FOR UPDATES.
>
> http://www.postgresql.org/docs/8.0/static/explicit-
> locking.html#LOCKING-TABLES
>
> It was somewhat challenging today to try to track down a pervasive
> locking issue related to a table not directly referenced in a stored
> procedure but that was referenced by a key in a table that was being
> updated.
>
> I'm not sure how this changes with the new shared row locking
> implementation in 8.1...
>


8.1 will use _shared_ row locks for such cases.

--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

---------------------------(end of broadcast)---------------------------
TIP 1: if posting/reading through Usenet, please send an appropriate
subscribe-nomail command to majordomo@postgresql
.org so that your
message can get through to the mailing list cleanly

Sponsored Links





Also available: Server administration forum archive | Web Design forum archive | Software forum archive | Hardware reviews archive | Programming forum archive

Copyright 2008 droptable.com