ALTER TABLE workarounds

Does anyone have a master list of ALTER TABLE workarounds?  That is, ways
to manipulate the various pg_* tables to emulate 'missing' ALTER TABLE
commands like

ALTER TABLE DROP CONSTRAINT

ALTER TABLE DROP COLUMN

etc.


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Jeff Boes                                             vox 616.226.9550
Database Engineer                                     fax 616.349.9076
Nexcerpt, Inc.                                      jboes@nexcerpt.com