> > > It suppose to mean that NULLs are explicitly allowed in
> > > this field.
> > > Is this required by SQL-92?
> >
> > No, it's not required. This came up before with the examples from
> > "The Practical SQL Handbook". It would be nice to allow it, but there
> > was some reason why to do so would be non-trivial, which I forget.
> > Anyway, it's not in SQL-92.
> >
> Sorry, I don't understand why we need this feature. This is completely ou=
> t
> of standard.
>
> What's that mean ?
>
> - Is it a constraint to allow only NULL values ? (unuseful)
Useless? I NEED IT - URGENT - NOW - YESTERDAY.
Then I could create my tables with all required fields for
the future, but prevent that someone stores data in them
until I drop the constraint.
I vote for this :-)
Jan
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#========================================= wieck@debis.com (Jan Wieck) #