MySQL循环

create procedure p1(a int) 
begin
    declare sum int default 0;
    declare i int default 1;
while i<=a do -- 循环开始
    set sum=sum+i;
    set i=i+1;
end while; -- 循环结束
select sum;  
end

create procedure p2(a int)
begin
        declare sum int default 0;
        declare i int default 1;
        lName:loop -- 循环开始
            if i>a then 
                leave lName;  -- 判断成立，结束循环
            end if;
            set sum=sum+i;
            set i=i+1;
        end loop;  -- 循环结束
        select sum; 
end

create procedure p3(a int)
begin
        declare sum int default 0;
        declare i int default 1;
        repeat -- 循环开始
            set sum=sum+i;
            set i=i+1;
        until i>a end repeat; -- 循环结束
        select sum;
end