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CREATE TABLE TBL_TEST
(
ID NUMBER,
NAME VARCHAR2(100 BYTE),
PID NUMBER DEFAULT 0
);
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INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('1','10','0');
INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('2','11','1');
INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('3','20','0');
INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('4','12','1');
INSERT INTO TBL_TEST(ID,NAME,PID) VALUES('5','121','2');
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select * from TBL_TEST
start with id=1
connect by prior id = pid
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select * from TBL_TEST
start with id=5
connect by prior pid = id
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