使用 sql 查询公司的前五个请求

Question

我只需要列出数据库中对公司的前五个请求。我有两个表，分别名为"请求"和"公司"。给定公司可能会收到任意数量的请求。但是，我只需要查询并列出数据库中所有公司的前 5 个请求。

select top 5 *
from Request as r 
    INNER JOIN Company c
    ON r.Company_id=c.Company_ID

我已经完成了上述查询，但它只返回表中的前五个，而不是所有成员的前五个。如何更正我的查询？

Answer 1

    With r 
    as
    (select  *, row_number() over(partition by Company_id order by RequestDate) as rown
    from Request as)
    Select *
from r join Company c on c.Company_id=r.Company_id
    Where rown<=5

Answer 2

我认为您正在寻找公司表中存在的每个公司的前 5 个请求。在这种情况下，您可以在子选择中按公司rank()每个请求，然后选择排名<= 5的位置：

select company_id, request_id
from
    ( select c.company_id, r.request_id, rank() over (partition by c.company_id order by request_id) as Rank
    from request r
    inner join company c on
        r.company_id = c.company_id
    ) ranked
where rank <= 5

Answer 3

您需要按确定"第一性"的字段进行排序。 可能是这样的：

按 r.请求日期订购

Answer 4

;WITH companyrecords 
     AS (SELECT Company.*, 
                Row_number() OVER (partition BY r.Company_id ORDER BY 
                r.Company_id 
                ASC) 
                   AS 
                RowNumber 
         FROM   Request AS r 
                INNER JOIN Company c 
                  ON r.Company_id = c.Company_ID) 
SELECT * 
FROM   companyrecords 
WHERE  RowNumber <= 5