Re: cataloguing NOT NULL constraints

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>

To: Alvaro Herrera <alvherre@alvh.no-ip.org>

Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, exclusion@gmail.com, dean.a.rasheed@gmail.com, andrewbille@gmail.com, peter@eisentraut.org, pgsql-hackers@lists.postgresql.org, Justin Pryzby <pryzby@telsasoft.com>

Date: 2024-05-09T20:05:58Z

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 →

Revert structural changes to not-null constraints
- 6f8bb7c1e961 17.0 landed
Fix inconsistencies in error messages
- 21ac38f498b3 17.0 landed
Disallow direct change of NO INHERIT of not-null constraints
- d45597f72fe5 17.0 landed
Disallow NO INHERIT not-null constraints on partitioned tables
- 13daa33fa5a6 17.0 landed
Better handle indirect constraint drops
- 0cd711271d42 17.0 cited
Don't try to assign smart names to constraints
- d72d32f52d26 17.0 cited
Fix restore of not-null constraints with inheritance
- d9f686a72ee9 17.0 landed
ATTACH PARTITION: Don't match a PK with a UNIQUE constraint
- cee8db3f680b 17.0 landed
Fix propagating attnotnull in multiple inheritance
- c3709100be73 17.0 landed
Check stack depth in new recursive functions
- b0f7dd915bca 17.0 landed
Move privilege check to the right place
- ac22a9545ca9 17.0 cited
Update information_schema definition for not-null constraints
- 3af721794272 17.0 landed
Fix not-null constraint test
- d0ec2ddbe088 17.0 landed
Disallow changing NO INHERIT status of a not-null constraint
- 9b581c534186 17.0 cited
Catalog not-null constraints
- b0e96f311985 17.0 cited
parallel_schedule: add comment on event_trigger test dependency
- c8e43c22be27 17.0 landed
Revert "Catalog NOT NULL constraints" and fallout
- 9ce04b50e120 16.0 landed
Adjust contrib/sepgsql regression test expected outputs.
- 76c111a7f166 16.0 landed
Fix table name clash in recently introduced test
- 728015a47016 16.0 landed
Catalog NOT NULL constraints
- e056c557aef4 16.0 landed
Change the rules for inherited CHECK constraints to be essentially the same
- cd902b331dc4 8.4.0 cited

On Wed, May 8, 2024 at 4:42 PM Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:
> I spent a long time trying to think how to fix this, and I had despaired
> wanting to write that I would need to revert the whole NOT NULL business
> for pg17 -- but that was until I realized that we don't actually need
> this NOT NULL NO INHERIT business except during pg_upgrade, and that
> simplifies things enough to give me confidence that the whole feature
> can be kept.

Yeah, I have to admit that the ongoing bug fixing here has started to
make me a bit nervous, but I also can't totally follow everything
that's under discussion, so I don't want to rush to judgement. I feel
like we might need some documentation or a README or something that
explains the takeaway from the recent commits dealing with no-inherit
constraints. None of those commits updated the documentation, which
may be fine, but neither the resulting behavior nor the reasoning
behind it is obvious. It's not enough for it to be correct -- it has
to be understandable enough to the hive mind that we can maintain it
going forward.

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