oracle 递归查询

试验代码

 1 with view_test as (
 2 
 3      select ‘A‘ AS ID,‘X‘ AS P_ID,‘C‘ AS C_ID,‘1‘ AS IND_EX FROM DUAL
 4      
 5      UNION
 6      select ‘C‘ AS ID,‘A‘ AS P_ID,‘B‘ AS C_ID,‘1_1‘ AS IND_EX FROM DUAL
 7      UNION
 8      select ‘B‘ AS ID,‘C‘ AS P_ID,‘A‘ AS C_ID,‘1_2‘ AS IND_EX FROM DUAL
 9      /*UNION
10      select ‘A‘ AS ID,‘B‘ AS P_ID,‘C‘ AS C_ID FROM DUAL*/
11      UNION
12      select ‘A‘ AS ID,‘B‘ AS P_ID,‘X‘ AS C_ID,‘1_3‘ AS IND_EX FROM DUAL
13      
14      UNION
15      select ‘C‘ AS ID,‘A‘ AS P_ID,‘D‘ AS C_ID, ‘2_1‘ AS IND_EX FROM DUAL
16      UNION
17      select ‘D‘ AS ID,‘C‘ AS P_ID,‘A‘ AS C_ID, ‘2_2‘ AS IND_EX FROM DUAL
18      UNION
19      select ‘A‘ AS ID,‘D‘ AS P_ID,‘X‘ AS C_ID, ‘2_3‘ AS IND_EX FROM DUAL
20      
35 )
36 
37   select 
38        sys_connect_by_path(ID,‘>‘) AS ID
39        ,sys_connect_by_path(IND_EX,‘>‘) as ind_ex 
40   from 
41        view_test 
42   start 
43         with P_ID = ‘X‘ 
44   connect by 
45           P_ID = prior ID  AND ID = prior C_ID  
46                /*AND  ID != prior P_ID */ AND prior C_ID != ‘X‘

1    >A    >1
2    >A>C    >1>1_1
3    >A>C>B    >1>1_1>1_2
4    >A>C>B>A    >1>1_1>1_2>1_3
5    >A>C    >1>2_1
6    >A>C>D    >1>2_1>2_2
7    >A>C>D>A    >1>2_1>2_2>2_3