Question

我有以下两个表

表A

     Name Location Group Value
     July   AAA    A    1
     Aug    BBB    B    2
     Sep    CCC    C    3
     Oct    DDD    D    4
     Nov    EEE    E    5

表AA

 Name Location Group Value1
     July   AAA    A    6
     Aug    BBB    B    7
     Jan    CCC    C    8
     Oct    DDD    D    9
     Nov    FFF    F    10

我想要以下结果

Name Location Group Value Value1
 July   AAA    A       1    6
 Aug    BBB    B       2    7
 Jan    CCC    C            8
 Sep    CCC    C       3    
 Oct    DDD    D       4    9
 Nov    EEE    E       5    
 Nov    FFF    F            10

到目前为止，我使用了以下查询，但我无法得到结果..

SELECT A.Name, A.Location, A.Gruppo, A.value, AA.value1
FROM A
Full Outer Join AA
ON A.LOCATION=AA.LOCATION
and
A.GRUPPO=AA.GRUPPO
and 
A.name = AA.NAME

查询的结果如下

 Name Location Gruppo value value 1
    July    AAA    A       1    6
    Aug     BBB    B       2    7
                                8
    Oct     DDD    D       4    9
                               10
    Sep     CCC    C       3    
    Nov     EEE    E       5

任何人都可以帮助我。

Answer 1

你没有得到你所得到的结果的原因是你没有告诉查询为连接条件中的列选择哪个列不为空。

例如，如果行同时出现在A和AA中（或仅出现在A中），那么a.name将不为空。但是，如果行仅出现在AA中，则a.name将为空。在这种情况下，您希望它显示aa.name，您可以使用COALESCE（或NVL）：

WITH a AS (SELECT 'July' NAME, 'AAA' LOCATION, 'A' "GROUP", 1 VALUE FROM dual UNION ALL
           SELECT 'Aug' NAME, 'BBB' LOCATION, 'B' "GROUP", 2 VALUE FROM dual UNION ALL
           SELECT 'Sep' NAME, 'CCC' LOCATION, 'C' "GROUP", 3 VALUE FROM dual UNION ALL
           SELECT 'Oct' NAME, 'DDD' LOCATION, 'D' "GROUP", 4 VALUE FROM dual UNION ALL
           SELECT 'Nov' NAME, 'EEE' LOCATION, 'E' "GROUP", 5 VALUE FROM dual),
    aa AS (SELECT 'July' NAME, 'AAA' LOCATION, 'A' "GROUP", 6 VALUE1 FROM dual UNION ALL
           SELECT 'Aug' NAME, 'BBB' LOCATION, 'B' "GROUP", 7 VALUE1 FROM dual UNION ALL
           SELECT 'Jan' NAME, 'CCC' LOCATION, 'C' "GROUP", 8 VALUE1 FROM dual UNION ALL
           SELECT 'Oct' NAME, 'DDD' LOCATION, 'D' "GROUP", 9 VALUE1 FROM dual UNION ALL
           SELECT 'Nov' NAME, 'FFF' LOCATION, 'F' "GROUP", 10 VALUE1 FROM dual)
-- end of mimicking your tables a and aa with data in them. See the SQL below:
SELECT coalesce(A.Name, aa.name) NAME,
       coalesce(A.Location, aa.location) LOCATION,
       COALESCE(A."GROUP", AA."GROUP") "GROUP",
       A.value,
       AA.value1
FROM   A
       Full Outer Join AA
         ON A.LOCATION = AA.LOCATION
            AND A."GROUP" = AA."GROUP"
            and A.name = AA.NAME;

NAME LOCATION GROUP      VALUE     VALUE1
---- -------- ----- ---------- ----------
July AAA      A              1          6
Aug  BBB      B              2          7
Jan  CCC      C                         8
Oct  DDD      D              4          9
Nov  FFF      F                        10
Sep  CCC      C              3 
Nov  EEE      E              5

Answer 2

您可以选择3次，其中一次使用内部，两次使用左边连接和排除。然后将它们全部合并到一个结果集中：

SELECT A.Name, A.Location, A.Gruppo, A.Value, AA.Value1
FROM A
inner join AA
    ON  A.Location = AA.Location
    and A.Gruppo = AA.Gruppo
    and A.Name = AA.Name
union all
SELECT A.Name, A.Location, A.Gruppo, A.Value, AA.Value1
FROM A
left outer join AA
    ON  A.Location = AA.Location
    and A.Gruppo = AA.Gruppo
    and A.Name = AA.Name
where Value1 is null
union all
SELECT AA.Name, AA.Location, AA.Gruppo, A.Value, AA.Value1
FROM AA
left outer join A
    ON  A.Location = AA.Location
    and A.Gruppo = AA.Gruppo
    and A.Name = AA.Name
where Value is null

Oracle查询结果未给出结果

2 个答案: