MySQL中利用存储过程求1-100的数之和

delimiter $
create procedure pro_sum1(out sum int)
comment '求1到100的数之和'
begin
declare num int default 0; -- begin end中的语句要加分号
set sum=0;
while num<=100 do
set sum=sum+num;
set num=num+1;
end while;
end $
delimiter;

call pro_sum1(@sum);
select @sum;

drop procedure pro_sum1;