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>, jian he <jian.universality@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2023-12-02T18:41:01Z
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 Thu, Nov 23, 2023 at 1:08 AM Peter Eisentraut <peter@eisentraut.org> wrote:
 > After further thought, I think the right solution is to change
 > btree_gist (and probably also btree_gin) to use the common RT* strategy
 > numbers.

Okay. That will mean bumping the version of btree_gist, and you must be running that version to use 
the new temporal features, or you will get silly results. Right? Is there a way to protect users 
against that and communicate they need to upgrade the extension?

This also means temporal features may not work in custom GIST opclasses. What we're saying is they 
must have an appropriate operator for RTEqualStrategyNumber (18) and RTOverlapStrategyNumber (3). 
Equal matters for the scalar key part(s), overlap for the range part. So equal is more likely to be 
an issue, but overlap matters if we want to support non-ranges (which I'd say is worth doing).

Also if they get it wrong, we won't really have any way to report an error.

I did some research on other extensions in contrib, as well as PostGIS. Here is what I found:

## btree_gin:

3 is =
18 is undefined

same for all types: macaddr8, int2, int4, int8, float4, float8, oid, timestamp, timestamptz, time, 
timetz, date, interval, inet, cidr, text, varchar, char, bytea, bit, varbit, numeric, anyenum, uuid, 
name, bool, bpchar

## cube

3 is &&
18 is <=>

## intarray

3 is &&
18 is undefined

## ltree

3 is =
18 is undefined

## hstore

3 and 18 are undefined

## seg

3 is &&
18 is undefined

## postgis: geometry

3 is &&
18 is undefined

## postgis: geometry_nd

3 is &&&
18 is undefined

I thought about looking through pgxn for more, but I haven't yet. I may still do that.
But already it seems like there is not much consistency.

So what do you think of this idea instead?:

We could add a new (optional) support function to GiST that translates "well-known" strategy numbers 
into the opclass's own strategy numbers. This would be support function 12. Then we can say 
translateStrategyNumber(RTEqualStrategyNumber) and look up the operator with the result.

There is not a performance hit, because we do this for the DDL command (create pk/uq/fk), then store 
the operator in the index/constraint.

If you don't provide this new support function, then creating the pk/uq/fk fails with a hint about 
what you can do to make it work.

This approach means we don't change the rules about GiST opclasses: you can still use the stranums 
how you like.

This function would also let me support non-range "temporal" foreign keys, where I'll need to build 
queries with && and maybe other operators.

What do you think?

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