Question

我有一个SQL查询，我想从课程表中选择idLesson列大于MAX的来自出勤表idLesson的行。如何更正此查询？

SELECT student.userid, lessons.idLesson, student.fee, lessons.datePassed 
    FROM student
    Inner JOIN `project_course`.group ON group.idGroup = student.idGroup
    Inner JOIN lessons ON group.idGroup=lessons.idGroup 
    Inner JOIN attendance ON lessons.idLesson>MAX(attendance.idLesson)
    group by lessons.idlesson;

Answer 1

这是根据您的解释修改的查询

其中idLesson列大于MAX来自idLesson的出勤率表

SELECT student.userid, lessons.idLesson, student.fee, lessons.datePassed 
    FROM student
    Inner JOIN `project_course`.group ON group.idGroup = student.idGroup
    Inner JOIN lessons ON group.idGroup=lessons.idGroup 
WHERE lessons.idLesson > 
  ( SELECT MAX(attendance.idLesson)
    FROM attendance
  )

在MySQL查询中使用MAX函数

1 个答案: