Question

我将表格作为与以下值的链接

++++++++++++++++++++++++++
+ company_id +  industry +
++++++++++++++++++++++++++
+     1      +    a      +
+     2      +    b      +
+     3      +    a      +
+     4      +    c      +
+     5      +    a      +
+     6      +    c      +
+     7      +    a      +
++++++++++++++++++++++++++

a有计数4，c有计数2，b有计数1

我希望返回

的查询

++++++++++++++++++++++++++
+ company_id +  industry +
++++++++++++++++++++++++++
+     1      +    a      +
+     3      +    a      +
+     5      +    a      +
+     7      +    a      +
+     4      +    c      +
+     6      +    c      +
+     2      +    b      +
++++++++++++++++++++++++++

Answer 1

下面的查询使用子查询，该子查询分别计算每个industry的记录数。然后它的结果再次返回到原始表上，并按子查询的总计数对记录进行排序。

SELECT  a.*
FROM    tableName a
        INNER JOIN
        (
            SELECT industry, COUNT(*) totalCount
            FROM    tableName
            GROUP BY industry
        ) b ON a.industry = b.industry
ORDER BY b.totalCount DESC, a.company_ID ASC

SQLFiddle Demo

要获得更快的效果，请在列INDEX上添加industry。

Answer 2

你也可以试试这个。它正在计算每个行业作为一个群体的出现。然后按该号码分组。（SQLFIDDLE是非常方便的工具）

Demo：

select a.company_id, a.industry,
      (select count(*) as cnt from tbl b
       where a.industry = b.industry) as order_by
 from tbl a
 order by order_by desc;

Mysql如何按最高计数列排序到最低

2 个答案: