MySQL 循环结构

一、循环结构类型
while、loop、repeat

二、循环控制
iterate 类似于 continue
leave 类似于 break

三、语法

1. while
   [标签: ] while 循环条件 do
   循环体
   end while [标签];

2. loop
   [标签: ] loop
   循环体
   end loop [标签];

3. repeat
   [标签: ] repeat
   循环体
   until 结束循环的条件
   end repeat [标签];

标签是可选的