124. View the Exhibit and examine the description of the EMPLOYEES table.
Evaluate the following SQL statement:
SELECT employee_id, last_name, job_id, manager_id, LEVEL
FROM employees START WITH employee_id = 101
CONNECT BY PRIOR employee_id=manager_id ;
Which two statements are true regarding the output of this command? (Choose
two.)
A. The output would be in top-down hierarchy starting with EMPLOYEE_ID having
value 101.
B. The output would be in bottom-up hierarchy starting with EMPLOYEE_ID
having value 101.
C. The LEVEL column displays the number of employees in the hierarchy under
the employee having the EMPLOYEE_ID 101.
D. The LEVEL column displays the level in the hierarchy at which the employee
is placed under the employee having the EMPLOYEE_ID 101.
Answer: AD
Topdown: 由上至下bottomup: 由下至上
做题的时候要仔细,LEVEL 是显示层次的
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