ocp-281

QUESTION NO: 281
Which of the following statements best describes Flashback Versions Query?

A. Flashback Versions Query is used to make changes to multiple versions of data that existed between
two points in time.
B. Flashback Versions Query is used to view all version changes on rows that existed between the time
the query was executed and a point in time in the past.
C. Flashback Versions Query is used to view version changes and the SQL to undo those changes on
rows that existed between two points in time.
D. Flashback Versions Query is used to view all version changes on rows that existed between two points
in time.
Answer: D
Flashback Versions Query does not change data at all, so option A is incorrect. B could be correct, but
only if one of the specified points in time was the current timestamp. Therefore, B is not the best
description. Option C is incorrect because Flashback Versions Query does not provide the SQL to undo
the changes.

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以下哪个陈述最能描述闪回版本查询？

D. 闪回版本查询是用来查看存在两个时间点上的行的所有版本变化。