On 2024-03-24 16:28 +0100, Thiemo Kellner wrote: > Am 24.03.2024 um 16:17 schrieb Tom Lane: > > > To do that, we'd have to remember that you'd said NULL, which we > > don't: the word is just discarded as a noise clause. Considering > > that this usage of NULL isn't even permitted by the SQL standard, > > that seems like a bit too much work. > > "Considering that this usage of NULL isn't even permitted by the SQL > standard" is in my opinion a strange argument. I don't know if the SQL standard ever allowed the NULL "constraint", but the 2003 revision (the oldest one that I've got) does not allow it: >From Part 2, 11.4 <column definition>: <column constraint> ::= NOT NULL | <unique specification> | <references specification> | <check constraint definition> Postgres only accepts it to be compatible with other RDBMS. [1] [1] https://www.postgresql.org/docs/current/sql-createtable.html#SQL-CREATETABLE-PARMS-NULL -- Erik
