OCP-1Z0-053-V12.02-69题

69.The EMP table exists in your schema. You want to execute the following query:
SELECT ename, sal
FROM emp
AS OF TIMESTAMP (SYSTIMESTAMP - INTERVAL '6' MINUTE)
WHERE ename = 'ALLEN';
What are the minimum requirements for the statement to execute successfully? (Choose all that apply)
A.ARCHIVELOG mode must be enabled
B.Row Movement must be enabled for the table
C.FLASHBACK must be set to ON for the database
D.The UNDO_MANAGEMENT parameter must be set to AUTO
E.The UNDO_RETENTION parameter must be set appropriately
Answer: DE
答案解析：
此题考查闪回查询，因为闪回查询是基于undo数据的，所以只要保证闪回查询的那个时间点有undo数据就能够查询成功