SQL Server聚合函數 - 如何？

Question

輸入表包含2列，即名稱和dept

+------+------+ 
| name | dept | 
+------+------+ 
| A | 123 | 
| B | 456 | 
| A | 789 | 
| C | 123 | 
| A | 456 | 
| B | 789 | 
+------+------+ 

輸出是

name 
----- 
A 

所以這裏A是在3個科指南（123，456，789）的工作。如何檢索在所有3個部門工作的姓名？

Answer 1

試試這個：

SELECT NAME 
FROM TABLE1 
GROUP BY NAME 
HAVING COUNT(DISTINCT DEPT)=(SELECT COUNT(DISTINCT DEPT) FROM TABLE1) 

Answer 2

這可以幫助你。

SELECT NAME 
FROM TABLE1 
GROUP BY NAME 
HAVING COUNT(DISTINCT DEPT) = 
          (
           SELECT COUNT(DISTINCT DEPT) 
           FROM TABLE1 
          ) 

Answer 3

下面是一個使用window function一個選項：

select name 
from (
    select name, count(distinct dept) cnt, 
      count(distinct dept) over() overallcnt 
    from yourtable 
    group by name 
) t 
where cnt = overallcnt