hi.
please check the attached latest version.
I did some minor cosmetic changes.
similar to commit 16a0039, we can just use ShareUpdateExclusiveLock to validate
existing not-valid not null constraints
for the below issue (should the last UPDATE fail or not),
I have already created a thread at [1].
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create domain d1 as int;
create table dt1(i int, c d1);
insert into dt1 values(1,2);
alter domain d1 add constraint cc check(value <> 2) not valid;
update dt1 set i = i + 1;
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[1]: https://postgr.es/m/CACJufxE2oFcLmrqDrqJrH5k03fv+v9=+-PBs-mV5WsJ=31XMyw@mail.gmail.com
