mysql - 如何加入自己的选择？

Question

1. 加入一个表本身是没有问题的。但是我需要自己加入一个创建的选择。第一个想法：使用临时表，但我只能打开一次。这是真的？

2. MySQL 是否足够聪明，可以计算始终只有一次相同术语的子选择？例如：

   join (select * from asdf where term) as one
   join (select * from asdf where term) as two
   ...
   join (select * from asdf where term) as ten
   

一般是怎么解决的？

Answer 1

您可以多次加入临时表

    select * into #temp from asdf where term
    ...
    join #temp as one
    join #temp as two
    ...
    join #temp as ten