Question

嗨，我刚接触sql，遇到这个问题。我按平均分数的升序和通过率的降序排序表子代码。代码是

select * 
from subjcode 
group by sno 
order by(select avg(score) from subjcode group by sno)asc ;

它从来没有工作过alwats说错误代码：1242。

下表名为subjcode：

Sno     cno     score
S001    C001    78.90
S001    C002    82.90
S001    C003    59.00
S002    C001    80.90
S002    C002    72.90
S003    C001    81.90
S003    C002    81.90
S004    C001    60.90

请有人帮帮我吗？谢谢

Answer 1

您不需要将AVG()放入另一个SELECT。只是：

ORDER BY AVG(score)

但是，在您进行分组时使用SELECT *是没有意义的。将从组中的随机行中选择所有其他列。你应该这样做：

SELECT sno, AVG(score) AS avg
FROM subjcode
GROUP BY sno
ORDER BY avg

如何在sql中按顺序使用avg

1 个答案: