Re: Re: Re: BUG #19351: in pg18.1,when not null exists in the table , and add constraint problem.

On 2025-Dec-13, yanliang lei wrote:

> Step 2: The execution of 'alter table test_null_20251210 add constraint xyzxyz not null c1' did not return any errors.
>
> after the execution of Step 2 , the executing user of the SQL
> statement "alter table test_null_20251210 add constraint xyzxyz not
> null c1" in the Step 2 will assume (because there was no error prompt
> in the Step 2 ) that the not null constraint has been successfully
> added to column c1, and the name of the constraint is xyzxyz.

> ----However, in reality, based on the execution results of the SQL
> database, the Step 2 did not actually succeed.

Yeah, that's fair -- we discussed this kind of behavior during
development and I was unsure about being strict about it, so avoided it.

This is mostly straightforward to fix, as attached (though the error
message needs work), but I hit a snag with multiple inheritance -- if
you apply this patch, you'll see failures in the pg_dump and pg_upgrade
tests. I don't have any ideas to fix this right now, but I'll keep
thinking about it.

--
Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/
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las patatas pelarían al hombre" (Ijon Tichy)