实例讲解Oracle数据库自带的几个触发器

--create or replace trigger MDSYS.sdo_drop_userafter drop on DATABASEdeclare    stmt varchar2(200);BEGIN     if dictionary_obj_type = 'USER' THEN       stmt := 'DELETE FROM SDO_GEOM_METADATA_TABLE ' ||               ' WHERE SDO_OWNER = ''' || dictionary_obj_name || ''' ';       EXECUTE IMMEDIATE stmt;    end if;end;---create or replace trigger SYS.aurora$server$startup after startup on database call dbms_java.server_startup -- create or replace trigger SYS.JIS$ROLE_TRIGGER$ after drop on database when (ora_dict_obj_type='ROLE')begin    sns_context.role_dropped(ora_dict_obj_name);    http_security_cascade.PRincipal_dropped(ora_dict_obj_name);  end;--删除前备份数据的器Create Or Replace Trigger YSPJ.T_Bill_reMain_DelBefore delete On bill_remainFOR EACH ROWbeginInsert into BILL_REMAIN_TIGERValues(:old.BILL_REMAINID,:old.BILL_TYPEID,:old.REMAIN_NUM,:old.ADD_TIME,:old.ORG_ID,:old.STATE,:old.BILL_ID,'删除记录',Sysdate,user);End;