添加子查询时，“此服务器版本在此位置选择无效...”

Question

我有一个语法错误，我不知道如何解决。我是MySQL的新手，错误消息让我感到困惑。

Select dept_name, total_student, total_instuctor, total_course
From department as d
    natural left join ( select dept_name count( dept_name ) as total_student
                        from student
                        group by dept_name) as s
    natural left join ( select dept_name count( dept_name ) as total_instructor
                        from instructor
                        group by dept_name) as i
    natural left join ( select dept_name count( dept_name ) as total_course
                        from course
                        group by dept_name) as c
Group By dept_name
Order By count( total_student ) desc;

当前收到错误消息“此服务器版本在此位置的选择无效，期望：'（'，WITH”加下划线的选择是第一个。

Answer 1

您忘记了子查询中所有的,选择项：

Select dept_name, total_student, total_instuctor, total_course
From department as d
    natural left join ( select dept_name, count( dept_name ) as total_student
                        from student
                        group by dept_name) as s
    natural left join ( select dept_name, count( dept_name ) as total_instructor
                        from instructor
                        group by dept_name) as i
    natural left join ( select dept_name, count( dept_name ) as total_course
                        from course
                        group by dept_name) as c
Group By dept_name
Order By count( total_student ) desc;