" ALTER TABLE DROP CONSTRAINT ; ALTER TABLE DROP CONSTRAINT ; ALTER TABLE ADD CONSTRAINT CHECK ; ALTER TABLE ADD CONSTRAINT CHECK ; DROP VIEW ; COMMIT; ALTER TABLE DROP INDEX ; ALTER TABLE DROP COLUMN ; ALTER TABLE ADD COLUMN DEFAULT NOT NULL ; ALTER TABLE ALTER COLUMN TYPE ; ALTER TABLE ALTER COLUMN DROP NOT NULL; ALTER TABLE ALTER COLUMN SET NOT NULL; ALTER TABLE ALTER COLUMN SET DEFAULT ; COMMENT ON COLUMN . IS ' '; ALTER TABLE ADD CONSTRAINT PRIMARY KEY ( , ); ALTER TABLE DROP PRIMARY KEY; " CREATE OR REPLACE VIEW ( , ) AS ; " CREATE TABLE ( NOT NULL DEFAULT , ); ALTER TABLE ADD CONSTRAINT PRIMARY KEY ( , ); ALTER TABLE DROP CONSTRAINT ; ALTER TABLE ADD CONSTRAINT FOREIGN KEY ( , ) REFERENCES ( , ); UNIQUE CREATE INDEX ON ( );