SELECT 每个 ID 只有一个值 - SQL 服务器

Question

我根本不知道这是否可行，我什至不确定如何 google。

我正在使用 SQL Server 2014。

现在我有一个 SP，它输出 table 数据，包括 MovementID、Vehicle、VehicleType 和 Total of sales。但它将所有车辆 id 和车辆类型组合在一起。

我需要分开车辆，我可以。问题是总数出现重复，或一式三份等。

那么，我怎样才能 select 每个 ID（示例中的 MovementID）只出现一次该列。

当然，我会继续努力，但如果有任何想法，我们将不胜感激。

[

Answer 1

您可以按 MovementID 对记录进行分区，然后生成 ROW_NUMBER for each row in the partition. Then, you can use IIF 以仅在行号为 1 时显示总数，即该行是分区中的第一行。它应该看起来像这样：

SELECT MovementID, VehicleID, VehicleType, IIF(rowno = 1, Total, NULL)
FROM
(
    SELECT MovementID, VehicleID, VehicleType, Total, 
     ROW_NUMBER() OVER (PARTITION BY MovementID ORDER BY MovementID) AS rowno
    FROM <WHAT_I_HAVE_NOW>
) tmp

Answer 2

您可以使用 LAG 查看上一行的值。

with q as (your query here)
select 
  movementid, vehicleid, vecicletype, 
  case when movementid = lag(movementid) over (order by movementid, vehicleid)
    then null else total
  end as total
from q
order by movementid, vehicleid;

Answer 3

您可以按照以下方式拆分和加入：

;with cte_vids as (
    select * from #tblmove
    cross apply udf_split( vehicleids, ',') 
), cte_vtypes as (
    select * from #tblmove
    cross apply udf_split( vehicletypes, ',')
)
select cid.movementid, cid.[value] as vehichleid, cty.[value] as vehicletype, 
    case when cid.rown = 1 then cid.total else null end as total 
from cte_vids cid join cte_vtypes cty
on cid.movementid = cty.movementid and cid.vehicleids = cty.vehicleids and cid.rown = cty.rown

答案如下：

+------------+------------+-------------+-------+
| movementid | vehichleid | vehicletype | total |
+------------+------------+-------------+-------+
|          1 | V01        | F           | 200   |
|          1 | V02        | T           | NULL  |
|          2 | V04        | V           | 140   |
|          3 | V03        | F           | 300   |
|          3 | V02        | F           | NULL  |
+------------+------------+-------------+-------+

我使用了一个你可以创建如下的函数：

CREATE Function dbo.udf_split( @str varchar(max), @delimiter as varchar(5) )
RETURNS @retTable Table 
( RowN int,
value varchar(max)
)
AS
BEGIN
DECLARE @xml as xml
    SET @xml = cast(('<X>'+replace(@str,@delimiter ,'</X><X>')+'</X>') as xml)
    INSERT INTO @retTable   
    SELECT RowN = Row_Number() over (order by (SELECT NULL)), N.value('.', 'varchar(MAX)') as value FROM @xml.nodes('X') as T(N)
RETURN
END

SELECT 每个 ID 只有一个值 - SQL 服务器

SELECT Only one value per ID - SQL Server

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