使用SYS_CONNECT_BY_PATH函数时Oracle ORA-30004,

Question

ORA-30004使用SYS_CONNECT_BY_PATH功能时,不能将分隔符作为列的一部分

操作:使用另一个不会出现在任何列值中的分隔符,然后重试.

错误:

select ...
Sys_Connect_By_Path(myVariable || ':' || mySecondVariable, ' --> ') "myNewVar",
...

作品:

select ...
Sys_Connect_By_Path(myVariable || ':' || mySecondVariable, ' -> ') "myNewVar",
...

在数据中我们发现了一些像这样的文本

• SomeText B--More Text
• SomeText A--More Text

由于数据中没有'-->'或没有' -->'',为什么第一个错误？第二个在前面和后面有一个空间.

Answer 1

那是因为它--是-->分离器的一部分而不是分离器的一部分->.

即使您的数据值有-->此查询也不应该出错.如下.

SQL> select Sys_Connect_By_Path('SomeText B-->More Text' || ':' || 'SomeText A-->More Text', ' --> ') "myNewVar"
from dual
connect by  rownum<=3;

myNewVar                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
----------------------------------------------------
--> SomeText B-->More Text:SomeText A-->More Text                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
--> SomeText B-->More Text:SomeText A-->More Text --> SomeText B-->More Text:SomeText A-->More Text                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
--> SomeText B-->More Text:SomeText A-->More Text --> SomeText B-->More Text:SomeText A-->More Text --> SomeText B-->More Text:SomeText A-->More Text

上面的分隔符是-->注意空格.这个空格被认为是分隔符的一部分,即chr(1)||chr(45)||chr(45)||chr(62)||chr(1).整个字符串不是数据或列值的一部分.

如下所示会出错

SQL> select Sys_Connect_By_Path('SomeText B-->More Text' || ':' || 'SomeText A-->More Text', '-->') "myNewVar"
from dual
connect by  rownum<=3;

ORA-30004: when using SYS_CONNECT_BY_PATH function, cannot have seperator as part of column value
30004. 00000 -  "when using SYS_CONNECT_BY_PATH function, cannot have seperator as part of column value"
*Cause:    
*Action:   Use another seperator which does not occur in any column value,
           then retry.

上面的分隔符是-->,注意没有空格即chr(45)||chr(45)||chr(62).整个字符串确实是数据或列值的一部分,因此也就是错误.

这是一个解决方案(未经测试的性能)

select regexp_replace(Sys_Connect_By_Path('SomeText B-->More Text' || ':' || 'SomeText A-->More Text', ' -> '),' -> ','-->') "myNewVar"
from dual
connect by  rownum<=3;

myNewVar                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
--------------------------------------
-->SomeText B-->More Text:SomeText A-->More Text                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
-->SomeText B-->More Text:SomeText A-->More Text-->SomeText B-->More Text:SomeText A-->More Text                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
-->SomeText B-->More Text:SomeText A-->More Text-->SomeText B-->More Text:SomeText A-->More Text-->SomeText B-->More Text:SomeText A-->More Text 

Explanation - Here(in the query above) -> (with space) is not part of the data here i.e. -->. Once the column is conected by path the regexp_replace replaces all occurences of -> with --> so this way you still get to have --> as your separator instead of ->.