Re: WIP: unique hash indexes

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: Neil Conway <neilc(at)samurai(dot)com>
Cc: PostgreSQL Patches <pgsql-patches(at)postgresql(dot)org>
Subject: Re: WIP: unique hash indexes
Date: 2003-12-01 04:55:30
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Your patch has been added to the PostgreSQL unapplied patches list at:

I will try to apply it within the next 48 hours.


Neil Conway wrote:
> Attached is a patch that implements unique hash indexes. Regression
> tests and docs have been updated (with the exception of
> src/backend/access/hash/README).
> This patches implements an improved version of the concurrency changes I
> outlined on -hackers a couple days ago: the separate lock for
> "right-of-insertion" into a bucket chain has been replaced by making use
> of existing lmgr lockmodes to get the behavior we need.
> I also took the opportunity to refactor the hash index code in a couple
> places by moving duplicated code into separate functions, fixed some
> typos in the README file, etc.
> I've tested this a little bit (it survives 100,000 single-user pgbench
> transactions, and 10 concurrent clients doing 1000 transactions each),
> but I need to do more testing in the future.
> As far as I know, the unique hash index code is functionally complete,
> but don't add this to the patch queue (it is obviously for 7.5, anyway),
> since I'm about to get started on some related hash index work, for
> which I'll submit a mega-patch containing everything. I just posted this
> here so that anyone who's interested can take a look at it -- comments
> are welcome.
> Thanks to Tom Lane, who was very helpful when I asked him code
> questions, including suggesting the improved concurrency design I
> mentioned above.
> Cheers,
> Neil

[ Attachment, skipping... ]

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> joining column's datatypes do not match

Bruce Momjian |
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