Question

以下代码适用于this fiddle

中显示的Oracle版本＆gt; = 9i

SELECT  T1.col1, T1.col3,count(T2.col1)
FROM    T1
LEFT JOIN T2
    ON T1.col3 = T2.col3
    AND ',' || T2.col2 || ',' like '%,' || T1.col1 || ',%'
GROUP BY T1.col1, T1.col3

但根据Oracle Left Outer Join文章，LEFT JOIN似乎无法使用Oracle 8i - 而且不幸的是我在8i工作。

对于=运算符，我知道等效代码

SELECT  T1.col1, T1.col3
FROM    T1
, T2
WHERE T1.col3 = T2.col3 (+)
--AND ',' || T2.col2 || ',' like '%,' || T1.col1 || ',%'

问题

但是我们如何为LIKE运算符指定OUTER JOIN条件。

注意：我相信，如果没有(+)，它将表现为该列的INNER JOIN。

更新

以下查询会出现ORA-00920: invalid relational operator错误

SELECT  T1.col1, T1.col3,count(T2.col1)
FROM    T1
,T2
WHERE     T1.col3 = T2.col3(+)
    AND (',' || T2.col2 || ',') LIKE ('%,' || T1.col1 || ',%')(+)
GROUP BY T1.col1, T1.col3

Answer 1

您可以尝试创建包含已修改列的子查询，然后按以下方式连接表：

Select  Mt1.T1_Col1, Mt1.T1_Col3,Count(Mt2.T2_Col1)
From
  (Select T1.Col1 As T1_Col1, T1.Col3 As T1_Col3, '%,' || T1.Col1 || ',%' As T1_Col1_New     From T1) Mt1, 
  (Select T2.Col1 As T2_Col1, T2.Col2 As T2_Col2, T2.Col3 As T2_Col3, ',' || T2.Col2 || ',' As T2_Col2_New From T2) Mt2
Where Mt1.T1_Col3 = Mt2.T2_Col3 (+)
And Mt1.T1_Col1_New Like Mt2.T2_Col2_New (+)
Group By Mt1.T1_Col1, Mt1.T1_Col3;

我在这里组合了内联子查询和外连接。

参考文献：

Answer 2

以下是来自fiddle

的代码

Select  Mt1.T1_Col1, Mt1.T1_Col3,Count(Mt2.T2_Col1)
From
  (Select T1.Col1 As T1_Col1,
          T1.Col3 As T1_Col3,
          '%,' || T1.Col1 || ',%' As T1_Col1_New
   From T1) Mt1
,
  (Select T2.Col1 As T2_Col1,
          T2.Col2 As T2_Col2,
          T2.Col3 As T2_Col3,
          ',' || T2.Col2 || ',' As T2_Col2_New 
   From T2) Mt2
WHERE Mt1.T1_Col3 = Mt2.T2_Col3 (+)
And Mt2.T2_Col2_New (+) LIKE Mt1.T1_Col1_New
--Mt2 should be on the left side of LIKE
Group By Mt1.T1_Col1, Mt1.T1_Col3;

Answer 3

我知道你不想听到这个，但是一旦有人说他们使用的是Oracle＆lt; 10g的版本，他们要问的任何问题的答案都是“升级”。在2014年，完全没有理由使用Oracle 8。

如何在Oracle 8i中指定可选的OUTER JOIN条件

3 个答案: