OCP-043 V$FLASHBACK_DATABSE_LOG & V$FLASHBACK_DATABASE_STAT

186. You executed the following query in your database:
FROM V$FLASHBACK_DATABASE_LOG;
What would you determine from the output?
A.the time when the last flashback operation in your database was performed
B.the time when the first flashback operation in your database was performed
C.a list of flashback operations performed in your database using SCN and time
D.the approximate time and the lowest system change number (SCN) to which you can flash back your
database


Answer: D


187. These are the details about V$FLASHBACK_DATABASE_STAT:
SQL> DESC V$FLASHBACK_DATABASE_STAT
Name Null? Type
BEGIN_
TIME DATE
END_TIME DATE
FLASHBACK_DATA NUMBER
DB_DATA NUMBER
REDO_DATA NUMBER
ESTIMATED_FLASHBACK_SIZE NUMBER
Which two statements regarding the V$FLASHBACK_DATABASE_STAT view are true? (Choose two.)
A.BEGIN_TIME is the time at which Flashback logging is enabled.
B.END_TIME is the time at which the query is executed on the view.

C.REDO_DATA is the number of bytes of redo data written during the interval.
D.This view contains information about flashback data pertaining to the last 24 hours.
E.FLASHBACK_DATA is the amount of flashback data generated since the database was opened.
Answer: CD

V$FLASHBACK_DATABASE_LOG

V$FLASHBACK_DATABASE_LOG displays information about the flashback data. Use this view to help estimate the amount of flashback space required for the current workload.

Column Datatype Description
OLDEST_FLASHBACK_SCN NUMBER Lowest system change number (SCN) in the flashback data, for any incarnation
OLDEST_FLASHBACK_TIME DATE Time of the lowest SCN in the flashback data, for any incarnation
RETENTION_TARGET NUMBER Target retention time (in minutes)
FLASHBACK_SIZE NUMBER Current size (in bytes) of the flashback data
ESTIMATED_FLASHBACK_SIZE NUMBER Estimated size of flashback data needed for the current target retention



V$FLASHBACK_DATABASE_STAT

V$FLASHBACK_DATABASE_STAT displays statistics for monitoring the I/O overhead of logging flashback data. This view also displays the estimated flashback space needed based on previous workloads.

Column Datatype Description
BEGIN_TIME DATE Beginning of the time interval
END_TIME DATE End of the time interval
FLASHBACK_DATA NUMBER Number of bytes of flashback data written during the interval
DB_DATA NUMBER Number of bytes of database data read and written during the interval
REDO_DATA NUMBER Number of bytes of redo data written during the interval
ESTIMATED_FLASHBACK_SIZE NUMBER Value of ESTIMATED_FLASHBACK_SIZE in V$FLASHBACK_DATABASE_LOG at the end of the time interval

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