Question

示例数据：

Serial | Name
-------------------------
     1 |  aaaa
     1 |  bbbb
     1 |  cccc
     2 |  aaaa
     3 |  bbbb
     3 |  aaaa
     3 |  cccc
     4 |  bbbb
     4 |  cccc

如果我按serial分组，我有4组。

Serial | record count in group |  name in group |
----------------------------------------
    1  |                    3  | aaaa,bbbb,cccc |
    2  |                    1  |           aaaa |
    3  |                    3  | aaaa,bbbb,cccc |
    4  |                    2  |      bbbb,cccc |

并按record count in group分组

repeat count | name in record count | repeat repeat count |
----------------------------------------------------------|
           1 |                 aaaa |                   1 |
           2 |            bbbb,cccc |                   1 |
           3 |       aaaa,bbbb,cccc |                   2 |

在所有组数据之后，我想要这样:(最后的结果是我期望的）

如何实现以下目标？

| Name | record count in group | Available Count |
|------------------------------------------------|
| aaaa |                     3 |               2 | (there are 2 aaaa in 3 combinations)
|------------------------------------------------| 
| aaaa |                     1 |               1 | (there is 1 aaaa in  1 combination)
|------------------------------------------------|
| bbbb |                     3 |               2 | (there is 2 bbb in  3 combinations)
|------------------------------------------------|
| bbbb |                     2 |               1 | ...
|------------------------------------------------|
| cccc |                     3 |               2 |
|------------------------------------------------|
| cccc |                     2 |               1 |
|------------------------------------------------|

我尝试了以下内容： SQL FIDDLE DEMO

SELECT Serial, COUNT(Serial) GroupCount, Name = 
    STUFF((SELECT ', ' + Name
       FROM your_table b 
       WHERE b.Serial = a.Serial 
       FOR XML PATH('')), 1, 2, '')
FROM your_table a
GROUP BY Serial

但是我应该编写一个搜索查询来查找我的预期结果

Answer 1

我不确定您的实际要求，但这可能是您想要的：

SELECT Name, cnt, COUNT(*)
FROM
 (
   SELECT Serial, Name,
      COUNT(*) OVER (PARTITION BY Serial) as cnt 
   FROM your_table
 ) a
GROUP BY Name, cnt

获取每个序列的行数作为窗口计数，然后按其分组：Fiddle

sql group by和get组合？

1 个答案: