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From: David Rowley <dgrowleyml@gmail.com>
Date: Wed, 15 Apr 2026 14:33:36 +1200
Message-ID: 
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Subject: Re: Add bms_offset_members() function for bitshifting Bitmapsets
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Chao Li <li.evan.chao@gmail.com>,
	PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
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On Wed, 15 Apr 2026 at 14:30, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> David Rowley <dgrowleyml@gmail.com> writes:
> > I'd not considered surprise-prone as an aspect. I understand we have
> > bms_join and bms_union, which do the same thing if you only care about
> > the value of the result and not what happens to the inputs.
>
> Sure, but bms_join is an optional optimization of the far safer
> bms_union operation.  It bothers me to create the optimized case
> but not the base case.

Hmm, yeah. That seems like a good argument for making a new set. I'll
go make it so.

David