Moving Redo Log Files - Quiz Explanation

The correct answers are indicated below, along with text that explains the correct answers.

1.	You need to drop a log file group, and all you know is that it contains a single member named`g:\oracle\oradata\coin\redocoin06a`. Which of the following commands will delete the group? Please select the best answer.
	A.	`alter database drop logfile group 'g:\oracle\oradata\coin\redocoin06a';`
	B.	`alter redo log drop group 'g:\oracle\oradata\coin\redocoin06a';`
	C.	`alter database drop logfile 'g:\oracle\oradata\coin\redocoin06a';`
	D.	`alter redo log drop file 'g:\oracle\oradata\coin\redocoin06a';`
	The correct answer is C. The`alter database drop logfile` command is the correct command to use. There is no such thing as an`ALTER REDO LOG` command, so neither B nor D is correct. There is an`alter database drop logfile group` command as shown in A, but that requires you to supply a group number, not a filename.

2.	Which of the following commands will add a member to group 5? Please select the best answer.
	A.	`alter logfile group 5 add member 'filename';`
	B.	`alter database alter group 5 add member 'filename';`
	C.	`alter logfile add member 'filename' to group 5;`
	D.	`alter database add logfile member 'filename' to group 5;`
	The correct answer is D. To add a member to group 5, you could use the command alter database add logfile member 'filename' to group 5. There is no alter logfile command, so A and C are incorrect. Answer B is incorrect because there is no alter group clause for the alter database command.

3.	You want to move a member to a new disk. You can't afford to disrupt your database users by stopping the database. Which of the following approaches can you take? Please select the best answer.
	A.	Move the file by executing the`alter database move logfile member` command.
	B.	Copy the file while the database is running, and then issue an`alter database rename file` command.
	C.	Create a new member file on the new disk, and then delete the unwanted member file from its location on the old disk.
	D.	While the database is running, issue an`alter database rename file` command to have Oracle move the file.
	The correct answer is C. You should create a new log file member on the new disk, and then delete the unwanted member from the old disk. Answer A represents an invalid command. Answer B would not work because you cannot safely copy a database file while the database is running, and you cannot issue an`alter database rename file` command while the database is open. Answer D won't work because the`alter database rename file` command doesn't move the file at the operating system level.