Am 24.03.24 um 16:28 schrieb Thiemo Kellner:
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.
If I understood correctly, only the NOT NULL expression gets
remembered, but the NULL gets discarded. No, I do not quite get it.
Somehow, it has to be decided whether to create a "check constraint"
or not, but this information is not available any more when creating
the primary key? Not even in some kind of intermediary catalogue?
the null-able constraint addition to a column is pointless because by
default all columns are nullable. definition as a primary key adds the
not null constraint.
Andreas
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Andreas Kretschmer
CYBERTEC PostgreSQL Services and Support
