Re: SET NULL / SET NOT NULL

> Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes:
> > I have throught of at least two problems with changing nullability.  The
> > first is primary keys.  I have to prevent people setting a
> column involved
> > in a PK to null, right?
>
> Probably so.

What about temporary tables - is there any reason they shouldn't be able to
modify a temporary table?

What about indices?  Will twiddling the nullability break indices on a table
in any way?

And foreign keys - foreign keys only have to reference UNIQUE, right?  The
nullability isn't an issue?

Lastly - in a multicolumn primary key, does EVERY column in the key need to
be NOT NULL?

Chris