Question

我有如下设置：

表格 - Tasks

| ResourceID |   Name   | T_SEQ | 
|    1       |  Res1    |   90  |
|    1       |  Res1    |   91  |
|    2       |  Res2    |   92  |

我正在运行以下内容：

select ResourceID, COUNT(ResourceID) 
from Tasks 
group by ResourceID

这表明Res1的计数为2，Res2的计数为1.

现在我想获得最低限度，所以在这种情况下我需要获得2的ResourceID，因为它只有1个工作，但我不知道该如何去做？

感谢任何可以提供帮助的人。

Answer 1

一种方法是order by和top：

select top 1 ResourceID, COUNT(ResourceID) 
from Tasks 
group by ResourceID
order by COUNT(ResourceID);

Answer 2

您可以使用CTE解决此问题。这将为您提供具有最小计数的所有行：

; WITH occurrences AS
(
    select ResourceID, COUNT(ResourceID) AS Counts
    from Tasks 
    group by ResourceID
)
, min_occurrences AS
(
    SELECT MIN(Counts) AS min_counts FROM occurrences
)
SELECT ResourceID FROM occurrences a
INNER JOIN min_occurrences b ON a.Counts = b.min_counts

选择最小计数的记录

2 个答案: