Error : CONNECT BY loop in user data

Question

Getting CONNECT BY loop in user data:
Table X  (sample data actually have 35K rows)
CODE             CASE              OLD_ID                NEW_ID            PERSON       AUTH
01              ab122         1234               0001             AU123     99393
07              vv353          7872               0919             FV982     78282
01              ab122         1982               9929             AU123     99393
04               hjsss         8839                8302            JK920     32320
01              ab122         0001               1982             AU123     99393
05              cg899         6728               32322           IKL020     65252
07              w353          0919                8282             FV982     78282
now I need to order this data comparing row values of old_id to new_id for each of the combinations of code, person, case
need output like below
Table X
CODE             CASE              OLD_ID                NEW_ID            PERSON       AUTH
01              ab122         1234               0001             AU123     99393
01              ab122         0001               1982             AU123     99393
01              ab122         1982               9929             AU123     99393
04               hjsss         8839                8302            JK920     32320
05              cg899         6728              32322           IKL020     65252
07              vv353          7872               0919             FV982     78282
07              w353          0919                8282            FV982     78282
to get this I am using:
--Query--
select * from table_x
start with old_id not in(
                                  select new_id
                                  from table_x
CONNECT BY old_id = PRIOR new_id
       AND   code   = PRIOR code
       AND   case   = PRIOR case
       AND   person = PRIOR person
--Query--
runs fine with sample data but the problem is when excute it with actual table that has 35K records..
Cause: The condition specified in a CONNECT BY clause caused a loop in the query, where the next record to be selected is a descendent of itself. When this happens, there can be no end to the query.
Action: Check the CONNECT BY clause and remove the circular reference.
Thanks,
AK

Answer 1

Hi,
CONNECT_BY_ISCYCLE is a pseudo-column that you can use in a CONNECT BY NOCYCLE query.  It's separate from the CONNECT BY clause.
Try this:
select  code, "CASE", person
,       SYS_CONNECT_BY_PATH (old_id, '/') AS path
from    table_x
where   CONNECT_BY_ISCYCLE = 1
start with  old_id not in (
                                  select new_id
                                  from table_x
CONNECT BY NOCYCLE old_id = PRIOR new_id
        AND        code   = PRIOR code
        AND        "CASE" = PRIOR "CASE"
        AND        person = PRIOR person
I hope this answers your question.
If not, post a little sample data (CREATE TABLE and INSERT statements, relevant columns only), and also post the results you want from that data.
Explain, using specific examples, how you get those results from that data.
Always say which version of Oracle you're using (e.g., 11.2.0.2.0).
See the forum FAQ: https://forums.oracle.com/message/9362002#9362002