trigger.sql

这是一个网上订票系统

--创建一个触发器，实现当用户退票的时候，向退款表refundment--
--中插入退款的所需的信息,规定退款金额为票价的80%--
SQL>@D:\schoolwork\数据库\第二次实验\trigger.sql;
create or replace trigger ReturnATicket before delete on speakfor
for each row
begin
  insert into refundment(id,ticketno,pass_name,money) (select ticket.
  id,ticket.ticketno,ticket.pass_name,ticket.price*0.8 from ticket
  where ticket.ticketno=:old.ticketno);
  update refundment set  (addr,postalcode)=(select addr,postalcode from 
  passenger where id=:old.id)
  where ticketno=:old.ticketno;
end ReturnATicket;