我这句mysql语句哪里错了呢? order by

做网上的mysql语句练习题,题目如下,

-- 13、查询和"01"号的同学学习的课程完全相同的其他同学的信息

我写的mysql语句如下,

SELECT student.`*` FROM student
LEFT JOIN score ON student.s_id = score.s_id
ORDER BY score.c_id
WHERE student.s_id <> '01'
GROUP BY student.s_id
HAVING GROUP_CONCAT(score.c_id) = '01,02,03'

报错如下,

经过尝试,把这句排序的语句去掉就能正常运行了,ORDER BY score.c_id

为什么order by 语句不能用在那里呢?

走过路过,请大神们指点迷津...

后面发现 group_concat 函数本来就有排序的功能了,我想要的排序功能可以按照如下语句实现,

SELECT student.* FROM student
LEFT JOIN score ON student.s_id = score.s_id
WHERE student.s_id <> '01'
GROUP BY student.s_id
HAVING GROUP_CONCAT(score.c_id ORDER BY score.c_id SEPARATOR '_') = '01_02_03'

猜你喜欢

转载自www.cnblogs.com/howmanyk/p/12242170.html