Question

我试图在主查询中获取最小日期值作为列，其中主查询和子查询具有内部联接，并且最小日期值取决于主查询联接中3列的分组

我在主查询Select语句中尝试了子查询，但是正如我的研究显示的那样，它们仅执行一次。我尝试了各种连接方式，但是无法获得逻辑或语法。我认为将cte组合使用可能有效，但无法弄清（对于那些学习新技巧的老狗来说，对于这些高级查询而言仍然太新了）

import itertools

list_1 =[[600,700], [500,200], [100,250], [300,100]]
list_2 = [[600,700,"A"], [500,600,"B"], [100,250,"C"]]
res = [l2[2] if (l1 and l2 and l1[:2] == l2[:2]) else False
       for l1, l2 in itertools.zip_longest(list_1, list_2)]
print(res)    # ['A', False, 'C', False]

到目前为止，我已经给了我每一行的Comp_Date。我需要实现的以便在以后的程序中可以在其他地方使用数据是

DECLARE

@StartBallDate date = '09-05-2009',
@StartLatDate date = '09-05-2009',
@Male int = 1,
@Female int = 4

SELECT T.*, E.StylID, C.PtsFirstRec

FROM dbo.tblPtsPerCompHistory AS T 
        INNER JOIN 
        (
        SELECT Min(Comp_Date) PtsFirstRec, Competition_Idx
        FROM tblCompetitions 
        GROUP BY Comp_Date, Competition_Idx
        ) C ON C.Competition_Idx = T.PtsCompID

        INNER JOIN tblEvtStructure AS E ON E.EvtStruct_Idx = T.PtsStructID

        WHERE E.SectnID Not Between 9 And 10 And (T.PtsMale = @Male Or T.PtsFemale = @Female And E.StylID = 1 And PtsFirstRec >= @StartBallDate) Or (T.PtsMale = @Male Or T.PtsFemale = @Female And E.StylID = 2 And PtsFirstRec >= @StartLatDate)

所以我所有行都是Ptsmale或PtsFemale，但最小日期值PtsFirstRec是配对的最早日期，也由E.StylID分组

Answer 1

这是另一个窗口函数：

DECLARE

@StartBallDate date = '09-05-2009',
@StartLatDate date = '09-05-2009',
@Male int = 1,
@Female int = 4

SELECT T.*, E.StylID, MIN(C.PtsFirstRec) OVER (PARTITION BY T.PtsMale      T.PtsFemale, E.StylID ORDER BY C.Comp_Date ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) [NewValue]

FROM dbo.tblPtsPerCompHistory AS T 
        INNER JOIN 
        (
        SELECT Min(Comp_Date) PtsFirstRec, Competition_Idx
        FROM tblCompetitions 
        GROUP BY Comp_Date, Competition_Idx
        ) C ON C.Competition_Idx = T.PtsCompID

        INNER JOIN tblEvtStructure AS E ON E.EvtStruct_Idx = T.PtsStructID

        WHERE E.SectnID Not Between 9 And 10 And (T.PtsMale = @Male Or T.PtsFemale = @Female And E.StylID = 1 And PtsFirstRec >= @StartBallDate) Or (T.PtsMale = @Male Or T.PtsFemale = @Female And E.StylID = 2 And PtsFirstRec >= @StartLatDate)

如果您包括测试数据，我们将能够确保代码确实可以正常工作。但这应该符合这些原则。

从子查询到主查询中选择“最小日期”值

1 个答案: