dbtry("delete from satellitemode where not exists (select 1 from satellite where satelliteid = satellite.id);"); $this->dbtry("ALTER TABLE satellitemode ADD CONSTRAINT satmode_satellite_FK FOREIGN KEY (satelliteid) REFERENCES satellite (id) ON DELETE CASCADE ON UPDATE RESTRICT;"); } public function down() { $this->dbtry("alter table satellitemode drop foreign key satmode_satellite_FK;"); } function dbtry($what) { try { $this->db->query($what); } catch (Exception $e) { log_message("error", "Something gone wrong while altering FKs: ".$e." // Executing: ".$this->db->last_query()); } } }