> this is an additional defined constraint, correct?
Yes, it will add a constraint to your table that specifically works on that particualar field.
> is
> this constraint added automagically by pgadmin when
> you enter a length value or is this a different
> method to achieve a similar result?
I am not exactly sure what your question is, but the ALTER TABLE <...> is a Data Definition
statement. Once the statement comments, then any future attempts by any connection to
update/insert will blocked if the data doesn't meet the constraint criteria.
Regards,
Richard Broersma Jr.