Re: Dump-restore loosing 'attnotnull' bit for DEFERRABLE PRIMARY KEY column(s).

On Thu, 7 Mar 2024 at 17:32, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:
>
> This seems to work okay.
>

Yes, this looks good. I tested it against CREATE TABLE ... LIKE, and
it worked as expected. It might be worth adding a test case for that,
to ensure that it doesn't get broken in the future. Do we also want a
test case that does what pg_dump would do:

 - Add a NOT NULL constraint
 - Add a deferrable PK constraint
 - Drop the NOT NULL constraint
 - Check the column is still not nullable

Looking at rel.h, I think that the new field should probably come
after rd_pkindex, under the comment "data managed by
RelationGetIndexList", and have its own comment.

Also, if I'm nitpicking, the new field and local variables should use
the term "deferrable" rather than "deferred". A DEFERRABLE constraint
can be set to be either DEFERRED or IMMEDIATE within a transaction,
but "deferrable" is the right term to use to describe the persistent
property of an index/constraint that can be deferred. (The same
objection applies to the field name "indimmediate", but it's too late
to change that.)

Also, for neatness/consistency, the new field should probably be reset
in load_relcache_init_file(), alongside rd_pkindex, though I don't
think it can matter in practice.

Regards,
Dean