Re: Add SPLIT PARTITION/MERGE PARTITIONS commands

Alexander Korotkov <aekorotkov@gmail.com>

From: Alexander Korotkov <aekorotkov@gmail.com>
To: Pavel Borisov <pashkin.elfe@gmail.com>
Cc: Justin Pryzby <pryzby@telsasoft.com>, Dmitry Koval <d.koval@postgrespro.ru>, Alexander Lakhin <exclusion@gmail.com>, Robert Haas <robertmhaas@gmail.com>, pgsql-hackers@lists.postgresql.org
Date: 2024-04-28T00:59:37Z
Lists: pgsql-hackers

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 errcode in checkPartition()

  2. Fix usage of palloc() in MERGE/SPLIT PARTITION(s) code

  3. Implement ALTER TABLE ... SPLIT PARTITION ... command

  4. Implement ALTER TABLE ... MERGE PARTITIONS ... command

  5. Calculate agglevelsup correctly when Aggref contains a CTE.

  6. Use PqMsg_* macros in applyparallelworker.c.

  7. Restrict psql meta-commands in plain-text dumps.

  8. Ensure we have a snapshot when updating various system catalogs.

  9. Use specific collation where needed in new test

  10. Expand virtual generated columns in the planner

  11. Virtual generated columns

  12. Define PG_LOGICAL_DIR for path pg_logical/ in data folder

  13. Revert support for ALTER TABLE ... MERGE/SPLIT PARTITION(S) commands

  14. Avoid repeated table name lookups in createPartitionTable()

  15. Provide deterministic order for catalog queries in partition_split.sql

  16. Don't copy extended statistics during MERGE/SPLIT partition operations

  17. Fix the name collision detection in MERGE/SPLIT partition operations

  18. Fix regression tests conflict in 3ca43dbbb6

  19. Add permission check for MERGE/SPLIT partition operations

  20. Fix one more portability shortcoming in new test_pg_dump test.

  21. Inherit parent's AM for partition MERGE/SPLIT operations

  22. Add tab completion for partition MERGE/SPLIT operations

  23. Rename tables in tests of partition MERGE/SPLIT operations

  24. Make new partitions with parent's persistence during MERGE/SPLIT

  25. Document the way partition MERGE/SPLIT operations create new partitions

  26. Change the way ATExecMergePartitions() handles the name collision

  27. Grammar fixes for split/merge partitions code

  28. Checks for ALTER TABLE ... SPLIT/MERGE PARTITIONS ... commands

  29. Fix some grammer errors from error messages and codes comments

  30. Support TZ and OF format codes in to_timestamp().

  31. Support identity columns in partitioned tables

  32. Fix indentation in twophase.c

  33. Fix corner-case planner failure for MERGE.

  34. Doc: fix documentation example for bytea hex output format.

  35. Avoid repeated name lookups during table and index DDL.

Attachments

Hi, Pavel.

Thank you for the review.

On Fri, Apr 26, 2024 at 4:33 PM Pavel Borisov <pashkin.elfe@gmail.com> wrote:
> I've looked at the patchset:
>
> 0001 Look good.
> 0002 Also right with docs modification proposed by Justin.

Modified as proposed by Justin.  The documentation for the way new
partitions are created is now in separate patch.

> 0003:
> Looks like unused code
> 5268             datum = cmpval ? list_nth(spec->lowerdatums, abs(cmpval) - 1) : NULL;
> overridden by
> 5278                     datum = list_nth(spec->upperdatums, abs(cmpval) - 1);
> and
> 5290                     datum = list_nth(spec->upperdatums, abs(cmpval) - 1);
>
> Otherwise - good.

Fixed, thanks.

> 0004:
> I suggest also getting rid of thee-noun compound words like: salesperson_name. Maybe salesperson -> clerk? Or maybe use the same terms like in pgbench: branches, tellers, accounts, balance.

Thank you, but I'd like to prefer keeping these modifications simple.
It's just regression tests, we don't need to have perfect naming here.
My intention is to fix just obvious errors.

> 0005: Good
> 0006: Patch is right
> In comments:
> +      New partitions will have the same table access method,
> +      same column names and types as the partitioned table to which they belong.
> (I'd suggest to remove second "same")

Documentation is modified per proposal by Justin.  Thus double "same"
is already gone.

> Tests are passed. I suppose that it's better to add similar tests for SPLIT/MERGE PARTITION(S)  to those covering ATTACH/DETACH PARTITION (e.g.: subscription/t/013_partition.pl and regression tests)

The revised patchset is attached.  I'm going to push it if there are
no objections.

Thank you for your suggestions about adding tests similar to
subscription/t/013_partition.pl.  I will work on this after pushing
this patchset.

------
Regards,
Alexander Korotkov
Supabase