Horton

Re: SQL:2011 application time

Matthias van de Meent <boekewurm+postgres@gmail.com>

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From: Matthias van de Meent <boekewurm+postgres@gmail.com>
To: Paul Jungwirth <pj@illuminatedcomputing.com>
Cc: Peter Eisentraut <peter@eisentraut.org>, Robert Haas <robertmhaas@gmail.com>, jian he <jian.universality@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2024-05-10T00:44:08Z
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. Rename gist stratnum support function

  2. Remove support for temporal RESTRICT foreign keys

  3. Cache NO ACTION foreign keys separately from RESTRICT foreign keys

  4. Fix NO ACTION temporal foreign keys when the referenced endpoints change

  5. Improve whitespace in without_overlaps test

  6. Tests for logical replication with temporal keys

  7. Support for GiST in get_equal_strategy_number()

  8. Make the conditions in IsIndexUsableForReplicaIdentityFull() more explicit

  9. Replace get_equal_strategy_number_for_am() by get_equal_strategy_number()

  10. Improve internal logical replication error for missing equality strategy

  11. Simplify IsIndexUsableForReplicaIdentityFull()

  12. Fix ALTER TABLE / REPLICA IDENTITY for temporal tables

  13. doc: Update pg_constraint.conexclop docs for WITHOUT OVERLAPS

  14. doc: Add PERIOD to ALTER TABLE reference docs

  15. doc: Add WITHOUT OVERLAPS to ALTER TABLE reference docs

  16. Add temporal FOREIGN KEY contraints

  17. Add temporal PRIMARY KEY and UNIQUE constraints

  18. Add stratnum GiST support function

  19. Avoid crashing when a JIT-inlined backend function throws an error.

  20. Revert temporal primary keys and foreign keys

  21. Fix ON CONFLICT DO NOTHING/UPDATE for temporal indexes

  22. Add test for REPLICA IDENTITY with a temporal key

  23. Use half-open interval notation in without_overlaps tests

  24. Use daterange and YMD in without_overlaps tests instead of tsrange.

  25. Rename pg_constraint.conwithoutoverlaps to conperiod

  26. Fix comment on gist_stratnum_btree

  27. Add missing TAP test name

  28. Improve error handling of HMAC computations

  29. Rename functions to avoid future conflicts

Hi,

I haven't really been following this thread, but after playing around
a bit with the feature I feel there are new gaps in error messages. I
also think there are gaps in the functionality regarding the (lack of)
support for CREATE UNIQUE INDEX, and attaching these indexes to
constraints.

pg=# CREATE TABLE temporal_testing (
pg(#  id bigint NOT NULL
pg(#    generated always as identity,
pg(#  valid_during tstzrange
pg(# );
CREATE TABLE
pg=# ALTER TABLE temporal_testing
pg-#  ADD CONSTRAINT temp_unique UNIQUE (id, valid_during WITHOUT OVERLAPS);
ALTER TABLE
pg=# \d+ temp_unique
                         Index "public.temp_unique"
    Column    |    Type     | Key? |  Definition  | Storage  | Stats target
--------------+-------------+------+--------------+----------+--------------
 id           | gbtreekey16 | yes  | id           | plain    |
 valid_during | tstzrange   | yes  | valid_during | extended |
unique, gist, for table "public.temporal_testing"
-- ^^ note the "unique, gist"
pg=# CREATE UNIQUE INDEX ON temporal_testing USING gist (id, valid_during);
ERROR:  access method "gist" does not support unique indexes

Here we obviously have a unique GIST index in the catalogs, but
they're "not supported" by GIST when we try to create such index
ourselves (!). Either the error message needs updating, or we need to
have a facility to actually support creating these unique indexes
outside constraints.

Additionally, because I can't create my own non-constraint-backing
unique GIST indexes, I can't pre-create my unique constraints
CONCURRENTLY as one could do for the non-temporal case: UNIQUE
constraints hold ownership of the index and would drop the index if
the constraint is dropped, too, and don't support a CONCURRENTLY
modifier, nor an INVALID modifier. This means temporal unique
constraints have much less administrative wiggle room than normal
unique constraints, and I think that's not great.

Kind regards,

Matthias van de Meent.