From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <dgrowleyml@gmail.com>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Speeding up ruleutils' name de-duplication code, redux
In-reply-to: <CAApHDvqMRD10-HEK5eXZDgo1NqjizdSg8Taqbakno1kAxaNuyA@mail.gmail.com>
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Comments: In-reply-to David Rowley <dgrowleyml@gmail.com>
	message dated "Wed, 11 Sep 2024 08:33:59 +1200"
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Date: Tue, 10 Sep 2024 16:36:00 -0400
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David Rowley <dgrowleyml@gmail.com> writes:
> On Wed, 11 Sept 2024 at 03:06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> We could accomplish what you suggest by re-ordering the calls so that
>> we build the hash table before enlarging the array.  0001 attached
>> is the same as before (modulo line number changes from being rebased
>> up to HEAD) and then 0002 implements this idea on top.  On the whole
>> though I find 0002 fairly ugly and would prefer to stick to 0001.
>> I really doubt that scanning any newly-created column positions is
>> going to take long enough to justify intertwining things like this.

> I'm fine with that.  I did test the performance with and without
> v2-0002 and the performance is just a little too noisy to tell. Both
> runs I did with v2-0002, it was slower, so I agree it's not worth
> making the code uglier for.
> I've no more comments. Looks good.

Thanks for the review!  I'll go push just 0001.

			regards, tom lane