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create table test (Id char);
insert into test values('A');
1 rows affected
insert into test values('B');
1 rows affected
insert into test values('C');
1 rows affected
insert into test values('D');
1 rows affected
insert into test values('E');
1 rows affected
SELECT id, PRIOR id AS id2
FROM test
WHERE LEVEL = 2
CONNECT BY NOCYCLE PRIOR id > id
ORDER BY id, id2
| ID | ID2 |
|---|---|
| A | B |
| A | C |
| A | D |
| A | E |
| B | C |
| B | D |
| B | E |
| C | D |
| C | E |
| D | E |