Question

我在MySQL中遇到了以下问题的问题

问题出现在别名'T'

select course_id, sec_id, enrollment 
from (
    select course_id, sec_id, count(ID) as enrollment
    from section natural join takes
    where semester = 'Fall' and year =2009
    group by course_id, sec_id
) as T
where enrollment = (select max(enrollment) from T);

Answer 1

如果你没有任何吸引力，我想你可能会得到类似下面的内容。

select course_id, sec_id, count(*) as enrollment
        from section s
        join takes t on s.sec_id = t.course_id
        where semester = 'Fall' and year =2009
        group by course_id, sec_id 
        order by count(*) desc 
        limit 1 
;

错误代码：1146。表'fe539.t'不存在

1 个答案: