MySQL ORDER BY 十进制值无效

Question

带有 order by 子句的 SQL 查询无法正常工作。

VALUES:
5.0000   
4.0000   
4.5000  
4.7500  
4.0000  
5.0000

查询：

SELECT  AVG(rating) as rating
FROM review
GROUP BY id
ORDER BY CAST(`rating` as signed) DESC

当我执行这个查询时，输出是：

我的评分栏是 int(10)。

Answer 1

您必须在 AVG(rating) 之前订购，而不是在 rating

之前订购

SELECT AVG(rating) as rating FROM review GROUP BY id ORDER BY AVG(rating) DESC

在您的例子中，别名和列具有相同的名称。为了避免混淆，你可以这样做：

SELECT AVG(rating) as avgrating FROM review GROUP BY id ORDER BY avgrating DESC

MySQL ORDER BY decimal value not working