重点是第二种用法,需要深入的了解。先看一个例子:mysql> explain select * from t_order; +----+-------------+---------+------+---------------+------+---------+------+--------+-------+ | id | s...
重点是第二种用法,需要深入的了解。先看一个例子:mysql> explain select * from t_order; +----+-------------+---------+------+---------------+------+---------+------+--------+-------+ | id | s...