Re: GROUP BY ROLLUP queries on views trigger full table scans (index usage not optimized)

Richard Guo <guofenglinux@gmail.com>

From: Richard Guo <guofenglinux@gmail.com>
To: Haowu Ge <gehaowu@bitmoe.com>
Cc: pgsql-bugs <pgsql-bugs@lists.postgresql.org>, Tom Lane <tgl@sss.pgh.pa.us>
Date: 2025-12-24T07:50:27Z
Lists: pgsql-bugs

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On Thu, Dec 18, 2025 at 5:56 PM Richard Guo <guofenglinux@gmail.com> wrote:
> Upon closer look, it seems that we do not need the syntactic scope
> check at all, as long as we ensure that phnullingrels is empty.  In
> this case, the PHV is either a no-op (from a reduced outer join) or
> used for identity separation (grouping sets).  In either case, the PHV
> is transparent regarding the value, so it should not prevent the
> underlying expression from matching the index.

Here is the updated version along the lines of this idea.

- Richard