Question

我有一个如下查询。表之间的关系是：

每辆卡车可能有多个司机。表列表将表Truck中的每一行与表Driver中的行连接起来。现在我想在一定条件下获得独特卡车的数量，以及在这种情况下独特卡车的总尺寸。

这就是我所拥有的：

SELECT t.Year AS [Year]
        , t.Month AS [Month]
        , t.Day AS [Day]

        -- Count will not count NULL
        , COUNT( DISTINCT (CASE WHEN (t.Sent = 1 AND r.Internal=1) THEN L.TruckId
                ELSE NULL
            END) ) AS [Count]

        , SUM(CASE WHEN (t.Sent = 1 AND r.Internal = 1) THEN t.Size
            END) AS [Size]

FROM Truck t
INNER JOIN List L ON t.Id = L.TruckId
        INNER JOIN Driver r ON L.DriverId = r.Id
GROUP BY t.Year, t.Month, t.Day

COUNT是正确的，但SUM不是。

我的问题是如何获得此SUM？ 我不想写2个查询并加入。

由于

Answer 1

您可以尝试如下查询：

; with cte as (
SELECT 
    DISTINCT
      t.Year AS [Year]
    , t.Month AS [Month]
    , t.Day AS [Day]
    , L.TruckId,
    , t.Size
FROM Truck t
INNER JOIN List L ON t.Id = L.TruckId
INNER JOIN Driver r ON L.DriverId = r.Id
WHERE t.Sent = 1 AND r.Internal=1
)
select 
      Year
    , Month
    , Day
    , count(TruckId) AS [Count]
    , sum(Size) AS [Size]
from cte 
group by Year, Month, Day

如何编写此SQL Server查询：在唯一行中添加值？

1 个答案: