> ALTER TABLE foo DROP CONSTRAINT foo_bar_id_fkey;
>
> ALTER TABLE foo ADD FOREIGN KEY (foo_bar_id_fkey) REFERENCES bar(id) ON
> DELETE CASCADE;
>
> Is there a more compact way to do this, perhaps with a single ALTER
> TABLE command?
Sure there is, you can preform multiple alterations in one statement:
ALTER TABLE foo DROP CONSTRAINT foo_bar_id_fkey,
ADD CONSTRAINT foo_bar_id_fkey
FOREIGN KEY (bar_fkey)
REFERENCES bar (id)
ON DELETE CASCADE;
regards,
Richard Broersma Jr.