每年最大行数（顶级）客户答案

【问题标题】：Max row count (top) customer per year每年最大行数（顶级）客户
【发布时间】：2014-07-26 10:15:24
【问题描述】：

为我的跳伞俱乐部做一些统计页面我有两个想要合并的 SQL 查询。一个显示了今年第一次加载时跳跃次数最多的前三名跳线：

select  top 3 ROW_NUMBER() OVER(ORDER BY count(1) desc) AS Nr 
        , vc.sCust as Name
        , count(1) as JumpsCount
from    dbo.ViewInvoice vi with(nolock)
join    dbo.viewCust vc
on      vi.wCustId = vc.wCustId
where   year(vi.dtProcess) = year(getdate())
        and vi.nMani = 1
group by vc.sCust 
order by count(1) desc

输出：

--  Nr  Name            JumpsCount
--  1   Tom Awesome         17
--  2   Alan Jackson        16
--  3   John Thebest        13

下一个查询显示了在数据库中跳跃的所有年份：

select  distinct year(vi.dtProcess) As Datum
from    dbo.ViewInvoice vi 
order by 1

输出：

--  Datum
--  2010
--  ...
--  2014

我想要的是获得一个将结果与如下输出合并的查询：

--  Datum   Nr  Name                Jumpscount
--  2010    1   Some OldVeteran         100
--  2010    2   Alan Jackson            96
--  2010    3   Gordon McGann           89
--  ...
--  2014    1   Tom Awesome             17
--  2014    2   Alan Jackson            16
--  2014    3   John Thebest            13

【问题讨论】：

标签： sql-server join count group-by

【解决方案1】：

更改为RANK，因此具有相同跳跃次数的跳线获得相同的位置。

WITH JumpsPerYear AS (
    SELECT YEAR(dtProcess) AS [Year]
          ,wCustId
          ,COUNT(1) AS JumpsCount
    FROM ViewInvoice
    WHERE nMani = 1 -- first load/manifest number
    GROUP BY YEAR(dtProcess)
            ,wCustId
)
,RankPerYear AS (
    SELECT [Year]
          ,wCustId
          ,RANK() OVER (PARTITION BY [Year] ORDER BY JumpsCount DESC) AS [Rank]
          ,JumpsCount
    FROM JumpsPerYear
)
SELECT RankPerYear.[Year] AS Datum
      ,RankPerYear.[Rank] AS Nr
      ,ViewCust.sCust AS Name
      ,RankPerYear.JumpsCount
FROM RankPerYear
     INNER JOIN ViewCust
         ON ViewCust.wCustId = RankPerYear.wCustId
WHERE RankPerYear.[Rank] <= 3
ORDER BY RankPerYear.[Year]
      ,RankPerYear.[Rank]

【讨论】：