Horton

Re: SQL:2011 application time

Paul A Jungwirth <pj@illuminatedcomputing.com>

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From: Paul Jungwirth <pj@illuminatedcomputing.com>
To: Peter Eisentraut <peter@eisentraut.org>
Cc: jian he <jian.universality@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, vignesh C <vignesh21@gmail.com>
Date: 2025-03-20T03:33:36Z
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

On 3/3/25 02:05, Peter Eisentraut wrote:
 > In the theory of the SQL standard, executing referential actions and checking the foreign-key
 > constraint are two separate steps.  So it kind of goes like this:
 >
 > 1. run command
 > 2. run any referential actions
 > 3. check that foreign key is still satisfied
 >
 > This is why the default referential action is called "NO ACTION": It just skips the step 2.  But it
 > still does step 3.
 >
 > This means that under RESTRICT and with my interpretation, the check for a RESTRICT violation in
 > step 2 can "ignore" the period part, but the step 3 still has to observe the period part.
 >
 > In the implementation, these steps are mostly combined into one trigger function, so it might be a
 > bit tricky to untangle them.

I understand that there are those separate steps. But it still doesn't make sense for RESTRICT to 
ignore the temporal part of the key. Actually, talking about "actions" reminds me of another reason: 
the effect of CASCASE/SET NULL/SET DEFAULT actions should also be limited to only the part of 
history that was updated/deleted in the referenced row. (This is why their implementation depends on 
FOR PORTION OF.) Otherwise a temporal CASCADE/SET NULL/SET DEFAULT would wreck havoc on your data. 
But if that's how these other actions behave, shouldn't RESTRICT behave the same way? Again, it's 
not clear why anyone would want a temporal foreign key that ignores its temporal attribute. And as I 
explained before, I don't think that's what a careful read of the standard says.

Yours,

-- 
Paul              ~{:-)
pj@illuminatedcomputing.com