Re: How to drop a NOT NULL column constraint? - Mailing list pgsql-general

Ed Loehr <eloehr@austin.rr.com> writes:
> I need to alter the table to get rid of the "NOT NULL" constraint on the
> 'id' column.  Can I do this using ALTER TABLE?

There isn't an ALTER TABLE variant for this at the moment, but you can
do it the hard way: reach in and change the attnotnull boolean in the
column's pg_attribute row.  The actual update would only require

    UPDATE pg_attribute SET attnotnull = 'f' WHERE
        attname = 'id' AND attrelid = whatever...

but I don't believe this will be noticed automatically by running
backends.  I think a VACUUM on your table afterwards would be sufficient
to force the backends to notice the change.

            regards, tom lane