MYSQL UPDATE LIMIT 更新限制语句用法

MYSQL更新时，要更新记录中某个区间的数据，只能用WHERE条件来限制了，用LIMIT只能限制更新多少条！
测试如下：

UPDATE user SET money = money + 10000 ORDER BY userid DESC LIMIT 5,20

上面这句测试了是错误的，MYSQL的UPDATE语句不能更新限制从第几条到第几条！
错误提示：#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '20' at line 1
只能用下面这样的语句了，要么你就用where条件语句来限制了

UPDATE user SET money = money + 10000 ORDER BY userid DESC LIMIT 20