CONSTRAINT valid_value CHECK (VALUE IN ('allow', 'to_cheap', 'to_expensive', 'deny'));
ALTER TABLE tb_tariffs ADD change_policy DM_TARIFF_CHANGE_POLICY DEFAULT 'allow';
+ALTER TABLE tb_tariffs ADD change_policy_timeout TIMESTAMP NOT NULL DEFAULT '1970-01-01 00:00:00';
+ALTER TABLE tb_tariffs ALTER COLUMN change_policy DROP DEFAULT;
+ALTER TABLE tb_tariffs ALTER COLUMN change_policy_timeout DROP DEFAULT;
UPDATE tb_info SET version = 8;