DELETE FROM cc_pref WHERE keystr = 'system_version'; INSERT INTO cc_pref (keystr, valstr) VALUES ('system_version', '2.2.1'); ALTER TABLE cc_block DROP CONSTRAINT cc_block_createdby_fkey; ALTER TABLE cc_block ADD CONSTRAINT cc_block_createdby_fkey FOREIGN KEY (creator_id) REFERENCES cc_subjs(id) ON DELETE CASCADE;