Question

我正在使用SQL Sever数据库，我正在编写一个查询来选择每个选项的计数＆＃RecordDate在调查的开始和结束日期中找到。如果相同的任何选项在开始和日期之间发现多次，那么即使这样也应该考虑一次。

tblOptions
----------------------------------
Option, RecardDate
----------------------------------  
o1 , 2016-01-01   
o1 , 2016-01-03   
o1 , 2016-05-08  
o2 , 2016-01-04   
o2 , 2016-01-01   
o2 , 2016-01-23     
o2 , 2016-05-15  
o3 , 2016-05-01  
o3 , 2016-05-02  
o3 , 2016-05-03     
o3 , 2016-04-04  
o3 , 2016-08-04


tblSurveys
----------------------------------
Surey, StartDate, EndDate
----------------------------------
s1 , 2016-01-01 , 2016-01-15
s2 , 2016-01-16 , 2016-01-31
s3 , 2016-05-01 , 2016-05-31

输出

Option,  Count 
-------------------
o1,  2             (Exp.:o1's recorddates found between two surveys star and end dates)     
o2,  3             (Exp.:o2's recorddates found between three surveys star and end dates)   
o3,  1             (Exp.:o3's recorddates found between one surveys star and end dates)

Answer 1

您可以通过将数据加在一起然后将它们组合在一起（下面的distinct选项）来实现这一目标，这样您就可以计算出独特的组合：

select [Option]                 -- You really should try to avoid using reserved
        ,count(1) as [Count]    -- words for your column names.
from (
    select distinct o.[Option]
                    ,s.Survey
                    ,s.StartDate
                    ,s.EndDate
    from @tblOptions o
        inner join @tblSurveys s
            on(o.RecardDate between s.StartDate and s.EndDate)
    ) a
group by [Option]

Answer 2

使用COUNT(DISTINCT column)

 SELECT  
     o.[Option], COUNT(DISTINCT Survey) [Count]
 FROM 
     tblOptions o
 INNER JOIN 
     tblSurveys s ON o.RecardDate BETWEEN s.StartDate AND s.EndDate
 GROUP BY 
     o.[Option]

Sql使用日期选择计数

2 个答案: