From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Geoghegan <pg@bowt.ie>
cc: pgsql-committers <pgsql-committers@lists.postgresql.org>
Subject: Re: pgsql: Make heap TID a tiebreaker nbtree index column.
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Comments: In-reply-to Peter Geoghegan <pg@bowt.ie>
	message dated "Wed, 20 Mar 2019 14:47:58 -0700"
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Date: Wed, 20 Mar 2019 17:50:45 -0400
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Peter Geoghegan <pg@bowt.ie> writes:
> On Wed, Mar 20, 2019 at 2:44 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> After trying it (against yesterday's sources) on my SELinux-capable
>> machine, I see no evidence that we need any output ordering changes
>> at all if we go this route.  This is probably unsurprising considering
>> that the old btree code used to provide mostly-reverse-insertion-order
>> scan order.

> That's good. I'm trying to fix it by hand right now, in the way that
> Andres suggested. It is both tedious and error-prone.

Yeah.  Don't do that.

After further thought I think I'll go with the alternate solution
(separate sortObjectAddresses function) as that could possibly have
other uses, and removing the "const" from performMultipleDeletions
seems a bit bletcherous.  Will push a fix in a few minutes.

			regards, tom lane