Horton

Re: Should I implement DROP INDEX CONCURRENTLY?

Simon Riggs <simon@2ndquadrant.com>

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From: Simon Riggs <simon@2ndQuadrant.com>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: Robert Haas <robertmhaas@gmail.com>, Daniel Farina <daniel@heroku.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2012-02-01T19:39:00Z
Lists: pgsql-hackers 
On Wed, Feb 1, 2012 at 7:31 PM, Peter Eisentraut <peter_e@gmx.net> wrote:
> On sön, 2012-01-29 at 22:01 +0000, Simon Riggs wrote:
>> Patch now locks index in AccessExclusiveLock in final stage of drop.
>
> Doesn't that defeat the point of doing the CONCURRENTLY business in the
> first place?

That was my initial reaction.

We lock the index in AccessExclusiveLock only once we are certain
nobody else is looking at it any more.

So its a Kansas City Shuffle, with safe locking in case of people
doing strange low level things.

-- 
 Simon Riggs                   http://www.2ndQuadrant.com/
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