> 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.


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