SQL:在单个结果行中进行组计数

问题描述

试试这个:

SELECT id, name, 
 (SELECT COUNT(name) 
   FROM markers im 
   WHERE state like 'OR' 
   GROUP BY name 
   HAVING im.name=m.name) as count
FROM markers m 
WHERE state like 'OR' 
GROUP BY name, id

解决方法

当我运行查询编号1时:

SELECT id,name,COUNT(name) AS count 
  FROM markers 
 WHERE state like 'OR' 
group by named

我得到以下结果:

id  name                count
14  Alsea               2
76  Applegate Valley    1
3   Ashland             9
64  Beaver              1
26  Bend                1
10  Carlton             2

很好,除了,我希望每个被计数名称的实例都以其各自的ID出现,如查询号2的结果所示:

SELECT id,COUNT(name) AS count 
  FROM markers 
WHERE state like 'OR' 
group by name,id

产生以下结果:

id  name                count
14  Alsea               1
28  Alsea               1
76  Applegate Valley    1
3   Ashland             1
13  Ashland             1
16  Ashland             1
20  Ashland             1
22  Ashland             1
43  Ashland             1
48  Ashland             1
51  Ashland             1
72  Ashland             1
64  Beaver              1
26  Bend                1
10  Carlton             1
27  Carlton             1

我是否可以运行一个查询,该查询将在每行中返回查询编号2的ID和名称以及查询编号1中的相应计数,如下所示?

id  name                count
14  Alsea               2
28  Alsea               2
76  Applegate Valley    1
3   Ashland             9
13  Ashland             9
16  Ashland             9
20  Ashland             9
22  Ashland             9
43  Ashland             9
48  Ashland             9
51  Ashland             9
72  Ashland             9
64  Beaver              1
26  Bend                1
10  Carlton             2
27  Carlton             2