Feedback-ID: ia2694551:Fastmail
Date: Thu, 23 Nov 2023 17:38:30 +0100
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Peter Eisentraut <peter@eisentraut.org>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: Catalog domain not-null constraints
Message-ID: <202311231638.httd7tqo45ux@alvherre.pgsql>
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On 2023-Nov-23, Peter Eisentraut wrote:

> This patch set applies the explicit catalog representation of not-null
> constraints introduced by b0e96f3119 for table constraints also to domain
> not-null constraints.

I like the idea of having domain not-null constraints appear in
pg_constraint.

> Since there is no inheritance or primary keys etc., this is much simpler and
> just applies the existing infrastructure to domains as well.

If you create a table with column of domain that has a NOT NULL
constraint, what happens?  I mean, is the table column marked
attnotnull, and how does it behave?  Is there a separate pg_constraint
row for the constraint in the table?  What happens if you do
ALTER TABLE ... DROP NOT NULL for that column?

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
"Por suerte hoy explotó el califont porque si no me habría muerto
 de aburrido"  (Papelucho)