Re: BUG #16386: drop contraint in inherited table is missing in pg_dump backup

On Fri, 24 Apr 2020 at 07:09, PG Bug reporting form <noreply(at)postgresql(dot)org>
wrote:

>
> create table b (aaa int primary key,bb date );
> create table A (id int primary key) inherits (B);
> alter table a alter column aaa drop not null;
>
> after i made pg_dump and pg_restore the not null contraint isexist on table
> a;
>
> It does not make sense to exclude a not null constraint on an inherited
table because column "aaa" can be null in table "a" but a SELECT in table
"b" will return a NULL for a primary key (ugh). It is just one of the ways
to shoot yourself in the foot. If you check CREATE TABLE synopsis, there
isn't NO INHERIT for not null constraints. Maybe it is worth adding a note
in CREATE TABLE.

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Euler Taveira http://www.2ndQuadrant.com/
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