您的位置: 首页  >  技术问答  >  如何在MySQL的左外连接中有序显示类别

如何在MySQL的左外连接中有序显示类别

分类: 技术问答 • 2022-02-25 23:05:42

如何在MySQL的左外连接中有序显示类别

问题描述：

How could I display this query, ordered by qid?

  $newcount=$db->get_results("
        SELECT  s2.qcategory, 
                s1.id, 
                count(s1.na) as na_count 
        FROM    (
                    select  distinct `qcategory` 
                    from    store 
                    where   survey_name='$userID' and 
                            dateone='$dateVal' and 
                            branch='$branch'
                ) s2 
                left join store s1 
                    on s1.`qcategory` = s2.`qcategory` and 
                        s1.`na` = '1' 
        group by 1 
        order by s1.qid");

如何按qid排序显示此查询？ p> 

  $ newcount = $ db-＆gt; get_results（“
 SELECT s2.qcategory，
 s1.id，
 count（s1.na）as na_count 
 FROM（
从商店中选择不同的`qcategory` 
  
其中survey_name ='$ userID'和
 dateone ='$ dateVal'和
 branch ='$ branch'
）s2 
在s1 .qcategory` = s2 .qcategory上的左连接商店s1 
  `和
 s1 .na` ='1'
按1 
顺序分组，由s1.qid“）; 
  code>  pre> 
  div>

答

since the data type is VARCHAR you need to convert it to numeric, eg

ORDER BY CAST(s1.qid AS SIGNED) ASC

答

u maybe want to order ASC or DESC

try this

     ORDER BY s1.qid  ASC

or 

   ORDER BY s1.qid  DESC

and why you make GROUP BY 1 ??

相关推荐