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Re: Row pattern recognition

Michael Paquier <michael@paquier.xyz>

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From: Michael Paquier <michael@paquier.xyz>
To: Henson Choi <assam258@gmail.com>
Cc: Tatsuo Ishii <ishii@postgresql.org>, jacob.champion@enterprisedb.com, david.g.johnston@gmail.com, vik@postgresfriends.org, er@xs4all.nl, peter@eisentraut.org, pgsql-hackers@postgresql.org
Date: 2026-01-19T23:40:43Z
Lists: pgsql-hackers 
On Mon, Jan 19, 2026 at 12:32:40AM +0900, Henson Choi wrote:
> I'm writing to document the detailed design of context absorption
> optimization in Row Pattern Recognition (RPR). This is mainly for
> future reference - honestly, I'm afraid I'll forget these details
> myself in a few months, and I'd rather have them written down
> somewhere public than buried in my notes. I don't want to repeat the
> mistake of famous mathematical theorems
> where brilliant ideas were lost because "the margin was too narrow
> to contain the proof" (yes, I'm looking at you, Fermat!). I certainly
> don't want future PostgreSQL hackers to spend the next 358 years
> trying to re-implement context absorption because the design rationale
> was lost. Fortunately, the PostgreSQL community has provided us with
> sufficient digital margins. :)

Note: this message is clearly AI-generated to me, and these are
usually super sloppy.  (I'd suggest to stop posting semi-generated
messages as they tend to be made of mostly unhelpful contents as they
lack judgement and context, but there's no rule against that AFAIK
around here, as well.)
--
Michael

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Adjust cross-version upgrade tests for seg_out() fix

  2. Rationalize error comments in partition split/merge tests

  3. Add fast path for foreign key constraint checks

  4. Fix assorted pretty-trivial memory leaks in the backend.

  5. Add temporal FOREIGN KEY contraints

  6. Add trailing commas to enum definitions

  7. Remove obsolete executor cleanup code