复杂的外部加入条件

Question

我有以下表格结构。

逻辑：如果一个工厂 - 部件号组合，如果它在@MHL表中有一个条目，则应该使用SumQty。

1. 我需要列出植物的总和值＆＃34; 11＆＃34;和＆＃34; DEF＆＃34; partnumber组合，我需要将总和列为50

CODE

DECLARE @MHL TABLE (LineNumber VarCHAR(5), PartNumber VARCHAR(10), Qty INT)


INSERT INTO @MHL VALUES ('10001','ABC',10)
INSERT INTO @MHL VALUES ('10002','ABC',100)
INSERT INTO @MHL VALUES ('10003','DEF',50)
INSERT INTO @MHL VALUES ('10005','KXY',25)
INSERT INTO @MHL VALUES ('10006','KXY',30)


DECLARE @MHP TABLE (PlantCode VarCHAR(5), LineNumber VARCHAR(5))
INSERT INTO @MHP VALUES ('20','10001')
INSERT INTO @MHP VALUES ('21','10002')
INSERT INTO @MHP VALUES ('80','10005')
INSERT INTO @MHP VALUES ('80','10006')


DECLARE @MasterPLantParts TABLE (PlantCode VarCHAR(5), PartNumber VARCHAR(10))

INSERT INTO @MasterPLantParts VALUES ('20','ABC')
INSERT INTO @MasterPLantParts VALUES ('21','ABC')
INSERT INTO @MasterPLantParts VALUES ('96','ABC')
INSERT INTO @MasterPLantParts VALUES ('11','DEF')
INSERT INTO @MasterPLantParts VALUES ('80','KXY')


SELECT M.PlantCode,M.PartNumber,SumQty
FROM @MasterPLantParts M
LEFT OUTER JOIN 
    (SELECT PartNumber, PlantCode, SUM(Qty) SumQty
     FROM @MHL H
     LEFT OUTER JOIN @MHP p
        on P.LineNumber = H.LineNumber
     GROUP BY PartNumber, PlantCode
    )T
ON T.PartNumber = M.PartNumber
AND T.PlantCode = M.PlantCode

当前结果



预期结果



问题

QtySum＆＃34; 50＆＃34;现在不来了。如何在SQL Server 2005中执行此操作？如果该方法可以在Oracle 8i中运行，那将是很好的

注意：即使@MHP中没有记录，我也需要从@MHL获得总和。但如果@MHP中有值，请从@MHP获取相关值，@ MHL关系

Answer 1

修改：

以下查询（比我发布的第一个查询更简单）可以获得所需的结果。首先，选择MasterPLantParts中的所有行（使用LEFT OUTER JOIN）。然后，用MHL进行连接。如果给定工厂的MHP中没有条目，则选择MHL的所有生产线。

select 
  mpp.PlantCode PlantCode, 
  mpp.PartNumber PartNumber,
  sum(MHL.Qty) as SumQty
from MasterPLantParts mpp
left outer join MHP on mpp.PlantCode = MHP.PlantCode
inner join MHL on MHL.LineNumber = MHP.LineNumber or (mpp.PartNumber = MHL.PartNumber and MHP.LineNumber is null)
group by mpp.PlantCode, mpp.PartNumber
order by mpp.PlantCode, mpp.PartNumber;

SQL Fiddle demo

Oracle 8i语法：

select 
  mpp.PlantCode PlantCode, 
  mpp.PartNumber PartNumber,
  sum(MHL.Qty) as SumQty
from MasterPLantParts mpp, MHP, MHL 
where mpp.PlantCode = MHP.PlantCode(+)
and (MHL.LineNumber = MHP.LineNumber or (mpp.PartNumber = MHL.PartNumber and MHP.LineNumber is null))
group by mpp.PlantCode, mpp.PartNumber
order by mpp.PlantCode, mpp.PartNumber;

<强>参考：

Oracle SQL*Plus Pocket Reference

Answer 2

我还没有在你的任何dbms上测试它，但是它应该对它们都进行微小的修复。

select PlantCode, PartNumber, sum(qty) 
from (
    select x.PlantCode, x.PartNumber, y.Qty 
    from MasterPLantParts x 
    join MHL y 
        on x.PartNumber = y.PartNumber 
    left join MHP z 
        on x.PlantCode = z.PlantCode 
    where z.PlantCode is null 
    union 
    select x.PlantCode, x.PartNumber, z.Qty 
    from MasterPLantParts x 
    join MHP y 
        on x.PlantCode = y.PlantCode 
    join mhl z 
        on y.LineNumber = z.LineNumber
) as T 
group by PlantCode, PartNumber;

PLANTCODE PARTNUMBER 3          
--------- ---------- -----------
11        DEF                 50
20        ABC                 10
21        ABC                100
80        KXY                 55
96        ABC                110

Answer 3

INSERT INTO @MHP VALUES ('91','what ever line number you wan to go here')   
INSERT INTO @MHP VALUES ('11','what ever line number you wan to go here')

在MHP中输出这些值时，您将始终具有空值，因为这就是左外连接所要做的。