为什么我没有在这里得到明确的分组？

Question

SELECT "STORE VISIT",STORE,USERVISITED 
FROM ECRSURVEY 
WHERE "STORE VISIT" > '2014-01-01     00:00:00.000'
GROUP BY STORE, "STORE VISIT", UserVisited

这不应该返回列STORE的不同分组吗？我的结果是同一个商店的多个条目。

Answer 1

获得明确的STORE：

SELECT STORE 
FROM   ECRSURVEY 
WHERE  "STORE VISIT" > '20140101'
GROUP BY STORE

或

SELECT DISTINCT STORE 
FROM   ECRSURVEY 
WHERE  "STORE VISIT" > '20140101'

或

如果您对其他两个字段进行聚合，那么您应该获得唯一的行

SELECT STORE 
       NumStoreVisit = COUNT("STORE VISIT"), 
       NumUserVisited = COUNT(UserVisited)
FROM   ECRSURVEY 
WHERE  "STORE VISIT" > '20140101'
GROUP BY STORE

但是如果您的数据结构如下，则您要求不可能：