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Re: Doubt about AccessExclusiveLock in ALTER TABLE .. SET ( .. ); - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Doubt about AccessExclusiveLock in ALTER TABLE .. SET ( .. );
Date
Msg-id CA+TgmoYy-AJ5-9sfb36-FFQ3tyTUnV7iDbpGPtuS873nttsySg@mail.gmail.com
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In response to Re: Doubt about AccessExclusiveLock in ALTER TABLE .. SET ( .. );  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: Doubt about AccessExclusiveLock in ALTER TABLE .. SET ( .. );  (Fabrízio de Royes Mello <fabriziomello@gmail.com>)
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On Tue, Aug 4, 2015 at 1:15 PM, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
> That opens up for lock escalation and deadlocks, doesn't it?  You are
> probably thinking that it's okay to ignore those but I don't necessarily
> agree with that.

Agreed.  I think we're making a mountain out of a molehill here.  As
long as the locks that are actually used are monotonic, just use > and
stick a comment in there explaining that it could need adjustment if
we use other lock levels in the future.  I presume all the lock-levels
used for DDL are, and will always be, self-exclusive, so why all this
hand-wringing?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

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