Re: [SQL] NULL

Bruce Momjian wrote:

> [Charset iso-8859-1 unsupported, filtering to ASCII...]
> >
> > How about this according to SQL standard:
> >
> > CREATE TABLE x { y integer NULL };
> >
> > It suppose to mean that NULLs are explicitly allowed in
> > this field.
> > Is this required by SQL-92?
>
> If I remember correctly, only NOT NULL is supported by SQL-92. Thomas
> talked about adding support for it in some limited cases for 7.0. There
> are shift/reduce cases if it were allowed everywhere.

Hmmm,

I can't see any shift/reduce conflicts if I place a

| NULL_P

case into the ColConstraintElem: definition right between the

| DEFAULT b_expr

and

| NOT NULL_P

cases. Could it be that this reason is out of date?

Jan

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