Horton

Re: Table AM Interface Enhancements

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Pavel Borisov <pashkin.elfe@gmail.com>
Cc: Alexander Korotkov <aekorotkov@gmail.com>, Melanie Plageman <melanieplageman@gmail.com>, Andres Freund <andres@anarazel.de>, Japin Li <japinli@hotmail.com>, Mark Dilger <mark.dilger@enterprisedb.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Michael Paquier <michael@paquier.xyz>, Heikki Linnakangas <hlinnaka@iki.fi>, Thomas Munro <thomas.munro@gmail.com>, Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: 2024-04-15T18:08:51Z
Lists: pgsql-hackers 
On Mon, Apr 15, 2024 at 12:37 PM Pavel Borisov <pashkin.elfe@gmail.com> wrote:
> In my understanding, the downside of 041b96802ef is bringing read_stream* things from being heap-only-related up to the level of acquire_sample_rows() that is not supposed to be tied to heap. And changing *_analyze_next_block() function signature to use ReadStream explicitly in the signature.

I don't think that really clarifies anything. The ReadStream is
basically just acting as a wrapper for a stream of block numbers, and
the API took a BlockNumber before. So why does it make any difference?

If I understand correctly, Alexander thinks that, before 041b96802ef,
the block number didn't necessarily have to be the physical block
number on disk, but could instead be any 32-bit quantity that the
table AM wanted to pack into the block number. But I don't think
that's true, because acquire_sample_rows() was already passing those
block numbers to PrefetchBuffer(), which already requires physical
block numbers.

-- 
Robert Haas
EDB: http://www.enterprisedb.com

Commits

  1. Remove extra comment at TableAmRoutine.scan_analyze_next_block

  2. revert: Generalize relation analyze in table AM interface

  3. Revert: Allow table AM to store complex data structures in rd_amcache

  4. Revert: Allow table AM tuple_insert() method to return the different slot

  5. Revert: Allow locking updated tuples in tuple_update() and tuple_delete()

  6. Revert: Let table AM insertion methods control index insertion

  7. Revert: Custom reloptions for table AM

  8. Provide a way block-level table AMs could re-use acquire_sample_rows()

  9. Custom reloptions for table AM

  10. Use streaming I/O in ANALYZE.

  11. Revert "Custom reloptions for table AM"

  12. Let table AM insertion methods control index insertion

  13. Generalize relation analyze in table AM interface

  14. Improve error message for tts_(virtual|minimal)_is_current_xact_tuple

  15. Add comments on some MinimalTupleSlots methods usage

  16. Add TupleTableSlotOps.is_current_xact_tuple() method

  17. Allow table AM tuple_insert() method to return the different slot

  18. Allow table AM to store complex data structures in rd_amcache