Question

编辑：重新提出整个问题。第一次带错了方式。

结果应该是：

MachineName | OrderNo | TaskID | Code | NettoProd | BrutoProd | DiffProd
=========================================================================
F1            123456    101      O      100000      125000      25000
F1            123456    102      P8     1000000     1250000     250000
F1            123456    103      P1     10000       12500       2500
F1            123456    104      P4     100000      125000      25000

JobSummary包含以下列：

StartDate 
TaskID

Route包含以下列：

OrderNo 
TaskID

Resource保存有关机器的数据

MachineID

如果我首先提供了所有细节，我已经添加了Kyle Gobel的部分，这是正确的答案。

我想要实现的是O根据taskID显示OrderNo与StartDate相关联的任务的第一个DateTime。表中的Route.No字段。

如果无法在一个JobSummary.StarDate语句中检查CASE和SELECT Resource.DESCRIPTION AS MachineName ,Route.OrderNo ,Route.TaskID ,CASE WHEN JobSummary.StartDate = (SELECT MIN(cr.StartDate) FROM JobSummary cr) THEN 'O' WHEN Route.No = 1 OR Route.No = 2 THEN 'P1' WHEN Route.No = 4 THEN 'P4' WHEN Route.No >= 8 THEN 'P8' ELSE '*FP*' END AS Code ,JobSummary.GoodProd As NettoProd ,JobSummary.GoodProd + JobSummary.SetupProd + JobSummary.WasteProd As BrutoProd ,(JobSummary.SetupProd + JobSummary.WasteProd) As DiffProd FROM Route JOIN Resource ON Resource.MachineID = Route.MachineID JOIN JobSummary ON JobSummary.TaskID = Route.TaskID AND JobSummary.MachineID = Route.MachineID，那么两者的单独列也会这样做。

查询

_x

Answer 1

您可以PARTITION BY与taskID一起使用StartDate根据OrderNo ROW_NUMBER()OVER(PARTITION BY Route.OrderNo ORDER BY JobSummary.StartDate ASC来识别第一条记录CREATE TABLE [JobSummary] (MachineID INT,TaskID INT,StartDate DATETIME,GoodProd NUMERIC(18,0),SetupProd NUMERIC(18,0),WasteProd NUMERIC(18,0)); CREATE TABLE [Route] (OrderNo INT,MachineID INT,TaskID INT,[No] INT); CREATE TABLE [Resource] (MachineID INT,DESCRIPTION CHAR(2)); INSERT INTO [Resource] VALUES(1,'F1'); INSERT INTO [Route] VALUES(123456,1,101,1); INSERT INTO [Route] VALUES(123456,1,102,9); INSERT INTO [Route] VALUES(123456,1,103,2); INSERT INTO [Route] VALUES(123456,1,104,4); INSERT INTO [JobSummary] VALUES(1,101,'20150101',100000,20000,5000); INSERT INTO [JobSummary] VALUES(1,102,'20150103',1000000,200000,50000); INSERT INTO [JobSummary] VALUES(1,103,'20150102',10000,2000,500); INSERT INTO [JobSummary] VALUES(1,104,'20150103',100000,20000,5000); ;WITH CTE AS ( SELECT Route.No ,Resource.[DESCRIPTION] AS MachineName ,Route.OrderNo ,Route.TaskID ,JobSummary.GoodProd As NettoProd ,JobSummary.GoodProd + JobSummary.SetupProd + JobSummary.WasteProd As BrutoProd ,(JobSummary.SetupProd + JobSummary.WasteProd) As DiffProd ,ROW_NUMBER()OVER(PARTITION BY Route.OrderNo ORDER BY JobSummary.StartDate ASC) rn FROM Route JOIN Resource ON Resource.MachineID = Route.MachineID JOIN JobSummary ON JobSummary.TaskID = Route.TaskID AND JobSummary.MachineID = Route.MachineID ) SELECT MachineName, OrderNo, TaskID, CASE WHEN rn = 1 THEN 'O' WHEN No IN (1,2) THEN 'P1' WHEN No = 4 THEN 'P4' WHEN No >= 8 THEN 'P8' ELSE '*FP*' END AS Code, NettoProd, BrutoProd, DiffProd FROM CTE ORDER BY OrderNo,TaskID < / p>

示例数据和结构

MachineName OrderNo TaskID  Code    NettoProd   BrutoProd   DiffProd
F1  123456  101 O   100000  125000  25000
F1  123456  102 P8  1000000 1250000 250000
F1  123456  103 P1  10000   12500   2500
F1  123456  104 P4  100000  125000  25000

<强>查询

this

<强>输出

undefined

ROW_NUMBER()

Answer 2

通过阅读您的问题，您可能正在寻找min聚合函数。

case 
   when route.startDate = (select min(r.startdate) from table r) then 'O'
   when route.no = 1 or route.no = 2 then 'P1'
   ....
end as code

Answer 3

使用ROW_NUMBER可能是一个很好的起点，但由于您只想检查第一个StartDate，因此最好使用MIN() OVER。您发布的查询只需要进行一些小改动（强调）：

SELECT Resource.DESCRIPTION AS MachineName
    ,Route.OrderNo
    ,Route.TaskID
    ,CASE
        WHEN JobSummary.StartDate = MIN(JobSummary.StartDate) OVER (PARTITION BY Route.OrderNo) THEN 'O'
        WHEN Route.No = 1 OR Route.No = 2 THEN 'P1'
        WHEN Route.No = 4 THEN 'P4'
        WHEN Route.No >= 8 THEN 'P8'
        ELSE '*FP*'
    END AS Code
    ,JobSummary.GoodProd As NettoProd
    ,JobSummary.GoodProd + JobSummary.SetupProd + JobSummary.WasteProd As BrutoProd
    ,(JobSummary.SetupProd + JobSummary.WasteProd) As DiffProd

FROM Route
JOIN Resource ON Resource.MachineID = Route.MachineID
JOIN JobSummary ON JobSummary.TaskID = Route.TaskID AND JobSummary.MachineID = Route.MachineID
;

也许PARTITION BY需要包含Resource.DESCRIPTION - 很难从一个小例子中说出来。

上述查询可能比ROW_NUMBER方法更快。这是因为ROW_NUMBER子集需要完全排序，而MIN（）OVER只能查找每个子集中的单个值。

另一方面，如果有可能您稍后需要第二行，第三行等特殊条件，那么ROW_NUMBER方法在这方面肯定会更灵活。

T-SQL CASE检查最年轻的日期，然后检查其他值

3 个答案: