> Pretty much when someone who cares about it enough comes along with
> a sufficient plan (and preferrably code) to implement it without breaking
> things would be my guess (especially given that AFAICS it's not part of
> either SQL92 or SQL99). Note that a sufficient plan would possibly
> involve a lot of things not directly involved with changing the type
> such as being able to deal with cached query plans for functions and
> such.
In other word, nobody cares about that at the moment, and so this will
not be implemented.
something i hate most about opensource movement are these comments like
"submit a patch". your staments are not that rough, but i'd need more
time to get into the code than to implement the feature.
so if this feature was never foreseen, than it might get a heavy task,
and it might be even havier in a few years to implement that.
even a tool could help to improve that. perhaps pgAdmin could be teached
to change a column's type by performing the steps it would need.
i'll submit a feature-request to the pgadmin team.