You have a database with the following tablespaces: SYSTEM, SYSAUX, UNDO, USERS, TEMP.
You want to"roll back" the data in the USERS tablespace to the way it looked yesterday. Which
tablespaces do you need to perform a point-in-time restore operation on in order to complete this task?
(Choose all that apply.)
A. SYSTEM
B. SYSAUX
C. UNDO
D. USERS
E. TEMP
F. This restore is not possible.
原文：http://www.cnblogs.com/Babylon/p/7815141.html