mysql中的错误1248

Question

我试图运行这个查询。

select * 
from (select * 
     from student 
     where dept_name= ’Comp. Sci’) 
     natural left outer join 
    (select * 
     from takes 
     where semester = ’Spring’ and year = 2009); 

但每次我拿到

error# 1248: every derived table must have its own alias. 

我曾尝试创建正在产生，但同样的错误每次出现的所有表的别名。

我该如何解决这个问题。我查了一些已经回答的问题，但没有运气。

Answer 1

试试这个:::

select * from 
(select * from student s where dept_name= ’Comp. Sci’) as tempLeft 
left join (select * from takes t where semester = ’Spring’ and year = 2009) on (// join condition) 

Answer 2

添加别名子查询：

select * 
from 
    (select * from student s where dept_name= 'Comp. Sci') as data1 
    natural left outer join (select * from takes t where semester = 'Spring' and year = 2009) as data2;