MySQL多列按序排列

Question

我正在尝试以升序运行此查询：

SELECT title,project_index 
FROM projectdetail  
WHERE project_index BETWEEN 1 AND 6 
ORDER BY title, project_index ASC;

我需要两列按升序排列，但上面的查询返回的结果中只有一列按ASC顺序排列。

Answer 1

升序是大多数(如果不是全部)数据库管理系统的默认，因此您的语句在这方面有点奇怪，但是，您可以通过向列添加说明符ASC或DESC来为每个单独的列指定顺序。

那么你的语句就会变成

SELECT  title
        , project_index 
FROM    projectdetail 
WHERE   project_index BETWEEN 1 AND 6 
ORDER BY 
        title ASC
        , project_index ASC

编辑

正如@Arvo & @Dems所提到的，目前您正在title上对first进行排序，并在project_index上对相同的标题进行排序。如果希望首先对project_index进行排序，则必须首先将其放在ORDER BY子句中。

然后，您的语句将变为

SELECT  title
        , project_index 
FROM    projectdetail 
WHERE   project_index BETWEEN 1 AND 6 
ORDER BY 
        project_index ASC
        , title ASC

因为ASC是默认的排序顺序，所以您可以将它们一起省略

SELECT  title
        , project_index 
FROM    projectdetail 
WHERE   project_index BETWEEN 1 AND 6 
ORDER BY 
        project_index
        , title

Answer 2

如果您使用的是mysql，请查看this。

就像他们说的，你可以使用SELECT * FROM t1 ORDER BY key_part1 DESC, key_part2 ASC;

Answer 3

按标题排序、project_index按标题排序；

 SELECT title,project_index 
 FROM projectdetail  
 WHERE project_index BETWEEN 1 AND 6 
 ORDER BY title ASC, project_index ASC;

您还可以添加更多列，如ORDER BY col1 ASC, col2 ASC, col3 DESC;