查询语句的"order by" 是基于什么算法进行排序的?

bananalx

查询语句的"order by" 是基于什么算法进行排序的?另外在哪能找到相关的资料.

bananalx

问这个问题真是有点傻,可能是工作时间长,脑子慢咧.查了一下mysql手册.如下:
   1. Read the rows that match the WHERE clause, as before.
   2. For each row, record a tuple of values consisting of the sort key value and row position, and also the columns required for the query.
   3. Sort the tuples by sort key value
   4. Retrieve the rows in sorted order, but read the required columns directly from the sorted tuples rather than by accessing the table a second time.