Subject: ROW SHARE/SELECT ... FOR UPDATE + foreign keys

From: "Thomas F. O'Connell" <[email-masked]>
Date: Thu, 21 Jul 2005 14:47:40 -0500

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...

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Thomas F. O'Connell
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---

From: Bruce Momjian <[email-masked]>
Date: Fri, 22 Jul 2005 01:13:22 -0400 (EDT)

> I'm not sure how this changes with the new shared row locking  

8.1 will use _shared_ row locks for such cases.

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