oracle 触发器

CREATE OR REPLACE TRIGGER test_trigger
  AFTER UPDATE OR DELETE OR INSERT on SEHR_USER
  for each row
begin
  CASE
    WHEN INSERTING THEN
      BEGIN
        insert into sys_users
          (id, name, real_name, reg_time, password, status)
        values
          (:new.id,
           :new.code,
           :new.name,
           sysdate,
           MD5(MD5(:new.name) || MD5(:new.password)),
           1);
      
      END;
    WHEN DELETING THEN
      BEGIN
        DELETE FROM sys_users WHERE ID = :OLD.ID;
      END;
    WHEN UPDATING THEN
      BEGIN
        UPDATE sys_users
           SET PASSWORD = MD5(MD5(:new.name) || MD5(:new.password))
         WHERE id = :OLD.ID;
      END;
  END CASE;
END;