Horton

Re: Eager aggregation, take 3

Richard Guo <guofenglinux@gmail.com>

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From: Richard Guo <guofenglinux@gmail.com>
To: Tender Wang <tndrwang@gmail.com>
Cc: Radim Marek <radim@boringsql.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2026-06-03T01:25:01Z
Lists: pgsql-hackers 
On Mon, Jun 1, 2026 at 4:57 PM Tender Wang <tndrwang@gmail.com> wrote:
> Richard Guo <guofenglinux@gmail.com> 于2026年6月1日周一 15:19写道：
> > So I'd rather fix it in eager_aggregation_possible_for_relation, right
> > next to the existing outer-join check, by rejecting a relation that
> > lies on the inner side of a semijoin/antijoin.  See attached.

> The attached LGTM.

Thanks for the review.  Pushed.

And thanks to Radim for the report and the well-contained repro.

- Richard

Commits

  1. Fix eager aggregation for semi/antijoin inner rels

  2. Cover additional errors and corner conditions in repack.c

  3. Fix volatile function evaluation in eager aggregation

  4. Fix collation handling for grouping keys in eager aggregation

  5. Rename apply_at to apply_agg_at for clarity

  6. Fix comment in eager_aggregate.sql

  7. Remove unnecessary include of "utils/fmgroids.h"

  8. Implement Eager Aggregation

  9. Allow negative aggtransspace to indicate unbounded state size

  10. Add macros for looping through a List without a ListCell.

  11. Account for the effect of lossy pages when costing bitmap scans.

  12. Fix a thinko in join_is_legal: when we decide we can implement a semijoin