Am 24.03.2024 um 15:54 schrieb Erik Wienhold:
> 
> This is required by the SQL standard: columns of a primary key must be
> NOT NULL.  Postgres automatically adds the missing NOT NULL constraints
> when defining a primary key.  You can verify that with \d test1 in psql.
To me, this behaviour, while correct, is not too concise. I wished, that 
PG issued a warning about a definition conflict. In PostgreSQL, a PK 
must always be not nullable, so explicitly defining on of a PK's columns 
as nullable is contradictory, one should get notified of.
The two dimes of Thiemo