Re: Add bms_offset_members() function for bitshifting Bitmapsets
Peter Eisentraut <peter@eisentraut.org>
From: Peter Eisentraut <peter@eisentraut.org>
To: David Rowley <dgrowleyml@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Chao Li <li.evan.chao@gmail.com>,
PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Date: 2026-04-15T19:17:12Z
Lists: pgsql-hackers
On 15.04.26 04:33, David Rowley wrote: > 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. Depending on what you end up doing, maybe a sprinkling of pg_nodiscard could be appropriate.