Explanation:
Before SWITCH DATA FILE command you should to issue SET NEW NAME command to rename the file restored in ‘DISK3/user_data01.dbf’ to ‘DISK2/user_data01.dbf’ because the SWITCH DATA FILE command is done on the files original position. Incorrect Answer:
1: You need to use this command to restore the file before renaming it.
2: You need to restore file on DISK2, not DISK3.
4: You are renaming file from ‘DISK3/user_data01.dbf’ to ‘DISK2/user_data01.dbf’, not vice versa, because the switch data file is done on the files original position.
Reference:
OCP Oracle 9i Database: Fundamentals II Exam Guide, Rama Velpuri, p. 324-325
Chapter 13: RMAN Complete Recovery

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