Mysql基础第二十七天,使用游标

Posted 2021-08-24 2019ab

游标

使用游标

call pressorders(); // 使用游标

创建游标

create procedure precessorders()
begin 
  declare done boolean default 0;
  declare t decimala(10,2);
  declare o int;
  declare ordernumbers cursor for select order_num from orders;
  declare continue bandler for sqlsate='0200' set done=1;
  create table if not exists ordertotals(order_num int,total decimal(10,2)
  open ordernumbers;
  repeat
    fetch ordernumbers into o;
    call ordertotal(o,1,t)
    insert into ordertotals values (o,t)
  until done end repeat;
  close ordernumbers;
  select * from ordertotals;
end;

打开和关闭游标

open ordernumbers; //打开
  repeat
    fetch ordernumbers into o;
    call ordertotal(o,1,t)
    insert into ordertotals values (o,t)
  until done end repeat;
  close ordernumbers; //关闭

删除游标

deallocate ordernumbers; // 删除游标