Re: Preventing index scans for non-recoverable index AMs - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: Preventing index scans for non-recoverable index AMs
Date
Msg-id 4949EDE6.8030500@enterprisedb.com
Whole thread Raw
In response to Re: Preventing index scans for non-recoverable index AMs  (Jeff Davis <pgsql@j-davis.com>)
Responses Re: Preventing index scans for non-recoverable index AMs  (Simon Riggs <simon@2ndQuadrant.com>)
Re: Preventing index scans for non-recoverable index AMs  ("Pavan Deolasee" <pavan.deolasee@gmail.com>)
List pgsql-hackers
Jeff Davis wrote:
> On Wed, 2008-12-17 at 17:10 -0600, Kenneth Marshall wrote:
>> On Wed, Dec 17, 2008 at 06:07:41PM -0500, Jaime Casanova wrote:
>>> On Wed, Dec 17, 2008 at 5:47 PM, Kenneth Marshall <ktm@rice.edu> wrote:
>>>> Rebuilding a hash index for the case
>>>> for which it is preferred (large, large tables) would be excrutiating.
>>>>
>>> there's such a situation?
>>>
>> As of 8.4, yes.
> 
> My understanding was that the hash index type never supported
> recoverability, and could require a rebuild on power failure.

Right, this is certainly not a new problem. It's not even a new problem 
in the context of replication or hot standby, because we already have 
the problem with PITR and file-based log shipping.

Also, it's not just a problem *during* the recovery. The index is just 
as corrupt after the recovery has finished.

I think we should just leave it alone for 8.4, and fix it properly in a 
future relase by implementing WAL-logging for hash indexes.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


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