Re: [COMMITTERS] pgsql: Remove arbitrary ALTER TABLE .. ADD COLUMN restriction.

Robert Haas <rhaas(at)postgresql(dot)org> writes:
> Remove arbitrary ALTER TABLE .. ADD COLUMN restriction.
> The previous coding prevented ALTER TABLE .. ADD COLUMN from being used
> with a non-NULL default in situations where the table's rowtype was being
> used elsewhere. But this is a completely arbitrary restriction since
> you could do the same operation in multiple steps (add the column, add
> the default, update the table).

This is not an "arbitrary restriction" because according to the SQL
standard those operations mean different things. In the first case you
get a column filled with the default value, in the second case you get a
column filled with nulls. And the latter case is the only one that
works properly with a rowtype.

Kindly revert this patch.

regards, tom lane