1

我的查询遇到逻辑问题。

我有两个表Table1和Table2，其中Table1包括：

  • value 求和
  • Id 分组
  • Code 持有外键Table2

Table2并由_

  • Code
  • Des 代码的文字描述

我要做的是 group by Table1.Id， full join on Table2.Code，但是，对于每个结果组，我想为查询生成的每个组显示 Table2 中的所有行。

示例代码：

SELECT
    Table2.Code, Table1.Id, Table2.DES, 
    SUM(Table1.Value) AS SUM_VAL
FROM 
(
    SELECT 'A' AS Code, 1 AS Id, 10 AS Value FROM DUAL UNION
    SELECT 'A' AS Code, 2 AS Id, 20 AS Value FROM DUAL UNION
    SELECT 'B' AS Code, 1 AS Id, 10 AS Value FROM DUAL UNION
    SELECT 'B' AS Code, 1 AS Id, 30 AS Value FROM DUAL UNION
    SELECT 'B' AS Code, 2 AS Id, 50 AS Value FROM DUAL UNION
    SELECT 'C' AS Code, 1 AS Id, 40 AS Value FROM DUAL UNION
    SELECT 'C' AS Code, 2 AS Id, 60 AS Value FROM DUAL UNION
    SELECT 'D' AS Code, 1 AS Id, 20 AS Value FROM DUAL

) Table1
FULL JOIN
(
    SELECT 'A' AS Code, 'This is A' AS DES FROM DUAL UNION
    SELECT 'B' AS Code, 'This is B' AS DES FROM DUAL UNION
    SELECT 'C' AS Code, 'This is C' AS DES FROM DUAL UNION
    SELECT 'D' AS Code, 'This is D' AS DES FROM DUAL
) Table2
ON Table1.Code = Table2.Code
GROUP BY
    Table2.Code, Table1.Id, Table2.DES
ORDER BY
    Table2.Code, Table1.Id ASC

结果：

A   1   This is A   10
A   2   This is A   20
B   1   This is B   40
B   2   This is B   50
C   1   This is C   40
C   2   This is C   60
D   1   This is D   20

要求的结果：

A   1   This is A   10
A   2   This is A   20
B   1   This is B   40
B   2   This is B   50
C   1   This is C   40
C   2   This is C   60
D   1   This is D   20
D   2   This is D   0    <- This is the target
4

3 回答 3

1

您必须以某种方式显示值对，(D,2)例如。通过制作一个包含可能值的代码列表并转换NULL为0：

  SELECT code.code,
         code.id,
         des.des,
         NVL (SUM (val.value), 0) sum_val
    FROM (SELECT 'A' code, 1 id FROM DUAL
          UNION
          SELECT 'A', 2 FROM DUAL
          UNION
          SELECT 'B', 1 FROM DUAL
          UNION
          SELECT 'B', 2 FROM DUAL
          UNION
          SELECT 'C', 1 FROM DUAL
          UNION
          SELECT 'C', 2 FROM DUAL
          UNION
          SELECT 'D', 1 FROM DUAL
          UNION
          SELECT 'D', 2 FROM DUAL) code
         INNER JOIN (SELECT 'A' code, 'This is A' des FROM DUAL
                     UNION
                     SELECT 'B', 'This is B' FROM DUAL
                     UNION
                     SELECT 'C', 'This is C' FROM DUAL
                     UNION
                     SELECT 'D', 'This is D' FROM DUAL) des
            ON code.code = des.code
         LEFT OUTER JOIN (SELECT 'A' code, 1 id, 10 VALUE FROM DUAL
                          UNION ALL
                          SELECT 'A', 2, 20 FROM DUAL
                          UNION ALL
                          SELECT 'B', 1, 10 FROM DUAL
                          UNION ALL
                          SELECT 'B', 1, 30 FROM DUAL
                          UNION ALL
                          SELECT 'B', 2, 50 FROM DUAL
                          UNION ALL
                          SELECT 'C', 1, 40 FROM DUAL
                          UNION ALL
                          SELECT 'C', 2, 60 FROM DUAL
                          UNION ALL
                          SELECT 'D', 1, 20 FROM DUAL) val
            ON code.code = val.code AND code.id = val.id
GROUP BY code.code, code.id, des.des
ORDER BY code, id

UNION ALL被使用是val因为可能会出现重复。

不需要FULL OUTER JOIN。

于 2015-06-10T09:54:43.377 回答
1

如果您想要 id 和 value 的所有组合，则使用cross join获取行并使用 aleft join来引入其余值：

select t2.code, i.value, t2.desc, coalesce(cnt, 0) as cnt
from (select distinct id from table1) i cross join
     table2 t2 left join
     (select id, value, count(*) as cnt
      from table1
      group by id, value
     ) iv
     on iv.id = i.id and iv.code = t2.code

这应该比手动列出所有组合要简单得多。

于 2015-06-10T10:50:56.530 回答
1 
SELECT
    Table2.Code, Table2.NAT, Table2.DES, 
    SUM(Table1.Value) AS SUM_VAL
FROM 
(
    SELECT 'A' AS Code, 'QA' AS Id, 10 AS Value FROM DUAL UNION
    SELECT 'A' AS Code, 'NQA' AS Id, 20 AS Value FROM DUAL UNION
    SELECT 'B' AS Code, 'QA' AS Id, 10 AS Value FROM DUAL UNION
    SELECT 'B' AS Code, 'QA' AS Id, 30 AS Value FROM DUAL UNION
    SELECT 'B' AS Code, 'NQA' AS Id, 50 AS Value FROM DUAL UNION
    SELECT 'C' AS Code, 'QA' AS Id, 40 AS Value FROM DUAL UNION
    SELECT 'C' AS Code, 'NQA' AS Id, 60 AS Value FROM DUAL UNION
    SELECT 'D' AS Code, 'QA' AS Id, 20 AS Value FROM DUAL

) Table1
FULL JOIN
(
    SELECT 'QA' NAT,'A' AS Code, 'This is A' AS DES FROM DUAL UNION
    SELECT 'QA' NAT,'B' AS Code, 'This is B' AS DES FROM DUAL UNION
    SELECT 'QA' NAT,'C' AS Code, 'This is C' AS DES FROM DUAL UNION
    SELECT 'QA' NAT,'D' AS Code, 'This is D' AS DES FROM DUAL
    UNION
    SELECT 'NQA' NAT,'A' AS Code, 'This is A' AS DES FROM DUAL UNION
    SELECT 'NQA' NAT,'B' AS Code, 'This is B' AS DES FROM DUAL UNION
    SELECT 'NQA' NAT,'C' AS Code, 'This is C' AS DES FROM DUAL UNION
    SELECT 'NQA' NAT,'D' AS Code, 'This is D' AS DES FROM DUAL
) Table2
on TABLE2.NAT = TABLE1.ID
      AND Table2.Code= Table1.Code
GROUP BY
    Table2.Code, Table2.NAT, Table2.DES
ORDER BY
    Table2.Code, Table2.NAT ASC
于 2015-06-11T05:14:21.660 回答