"Robert Haas" <robertmhaas(at)gmail(dot)com> writes:
> Although several people have said that they prefer the idea of using
> ALTER VIEW to make changes to views, no one has really expanded on the
> reasons for their preference.
Because it sidesteps the problem of tracking which column is supposed to
be which. If you try to do it through CREATE OR REPLACE VIEW, you have
to either be extremely restrictive (like probably not allow renaming
of columns at all), or write some AI-complete algorithm to guess at what
the user intended.
regards, tom lane