Tomas,
So for an API, 100% of the use cases I have for this feature would be
satisfied by:
ALTER TABLE ______ ALTER COLUMN _____ SET ORDER #
and:
ALTER TABLE _____ ADD COLUMN colname coltype ORDER #
If that's infeasible, a function would be less optimal, but would work:
SELECT pg_column_order(schemaname, tablename, colname, attnum)
If you set the order # to one where a column already exists, other
column attnums would get "bumped down", closing up any gaps in the
process. Obviously, this would require some kind of exclusive lock, but
then ALTER TABLE usually does, doesn't it?
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com