jian he <jian.universal...@gmail.com> 于2024年4月10日周三 14:10写道：
> On Wed, Apr 10, 2024 at 1:29 AM Alvaro Herrera <alvhe...@alvh.no-ip.org> > wrote: > > > > On 2024-Mar-29, Tender Wang wrote: > > > > > I think aboved case can explain what's meaning about comments in > > > dropconstraint_internal. > > > But here, in RemoveConstraintById() , we only care about primary key > case, > > > so NOT NULL is better to removed from comments. > > > > Actually, I think it's better if all the resets of attnotnull occur in > > RemoveConstraintById, for both types of constraints; we would keep that > > block in dropconstraint_internal only to raise errors in the cases where > > the constraint is protecting a replica identity or a generated column. > > Something like the attached, perhaps, may need more polish. > > > > DROP TABLE if exists notnull_tbl2; > CREATE TABLE notnull_tbl2 (c0 int generated by default as IDENTITY, c1 > int); > ALTER TABLE notnull_tbl2 ADD CONSTRAINT Q PRIMARY KEY(c0, c1); > ALTER TABLE notnull_tbl2 DROP CONSTRAINT notnull_tbl2_c0_not_null; > ALTER TABLE notnull_tbl2 DROP c1; > \d notnull_tbl2 > > last "\d notnull_tbl2" command, master output is: > Table "public.notnull_tbl2" > Column | Type | Collation | Nullable | Default > > --------+---------+-----------+----------+---------------------------------- > c0 | integer | | not null | generated by default as identity > > > > last "\d notnull_tbl2" command, applying > 0001-Correctly-reset-attnotnull-when-constraints-dropped-.patch > output: > Table "public.notnull_tbl2" > Column | Type | Collation | Nullable | Default > > --------+---------+-----------+----------+---------------------------------- > c0 | integer | | | generated by default as identity > Hmm, ALTER TABLE notnull_tbl2 DROP c1; will not call dropconstraint_internal(). When dropping PK constraint indirectly, c0's attnotnull was set to false in RemoveConstraintById(). -- Tender Wang OpenPie: https://en.openpie.com/
