Start with & Connect by
USER_TABLE
| EMPLYEE_ID | SUPERVISOR_ID |
| 001 | 002 |
| 002 | 003 |
| 003 |
START WITH emplyee_id = '001'
CONNECT BY emplyee_id = PRIOR supervisor_id
Output:
001
002
003
P.S CONNECT BY 欄位A = PRIOR 欄位B, 若欄位A與欄位B交換位置, 會變成向下追蹤, 若改成 CONNECT BY supervisor_id = PRIOR emplyee_id, 結果如下:
001
因為 001 沒有部屬
DEPT_TABLE
| DEPT_ID | UPPER_DEPT |
| A | B |
| B | C |
| C |
START WITH dept_id = 'A'
CONNECT BY dept_id = PRIOR upper_deptOutput:
A
B
C