For which two SQL statements can you use the Flashback Table feature to revert a table to its previous state？（）

单项选择题Why would you use the following FLASHBACK TABLE command？（）  FLASHBACK TABLE emp TO TIMESTAMP （’11：45’，’hh12：mi’）；

A.to undo the changes made to the EMP table since the specified time
B.to restore the EMP table that was wrongly dropped from the database
C.to view the transactions that have modified the EMP table since the specified time
D.to view the changes made to the EMP table for one or more rows since the specified time
E.to recover the EMP table to a point in time in the past by restoring the most recent backup

单项选择题You are working in an online transaction processing （OLTP） environment. You used the FLASHBACK TABLE command to flash back the CUSTOMERS table. Before executing the FLASHBACK TABLE command， the System Change Number （SCN） was 663571. After flashing back the CUSTOMERS table，you realize that the table is not in the correct state and the resultant changes are not what you had desired. So， you need to reverse the effects of the FLASHBACK TABLE command while ensuring that：  a） No other user data in the database is affected.  b） The operation takes the minimum possible time.  Which option would you choose？（）

A.use the ROLLBACK command with SCN 663571
B.perform Flashback Transaction Query with SCN 663571
C.execute the FLASHBACK DATABASE statement to retrieve the CUSTOMERS table as it was at SCN 663571
D.execute another FLASHBACK TABLE statement to retrieve the CUSTOMERS table as it was at SCN 663571

单项选择题On Monday， you dropped the DEPT table from your schema and then you re-created the DEPT table in your schema. On Wednesday， you have a requirement to restore the DEPT table from the recycle bin.  Which statement is correct？（）

A.You can restore the DEPT table by using the Oracle Flashback Drop feature， provided you use the RENAME TO clause.
B.You can restore the DEPT table by using the Oracle Flashback Drop feature and a system-generated name will be assigned to the restored table.
C.You cannot restore the DEPT table by using the Oracle Flashback Drop feature because a table with the name DEPT already exists in your schema.
D.You cannot restore the DEPT table by using the Oracle Flashback Drop feature because the contents of  the recycle bin are purged every 12 hours by default.

多项选择题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？ （）

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.

多项选择题You are using Oracle Database 10g. You performed an  incomplete recovery of your database and opened the database with the RESETLOGS option.  What is the effect of opening the database with the RESETLOGS option？（）

A.This operation resets the SCN for the database.
B.This operation creates a new incarnation of the database.
C.This operation moves all the redo log files to a different location.
D.This operation deletes the old redo log files and creates new redo log files.
E.This operation updates all current datafiles and online redo logs and all subsequent archived redo logs with a new RESETLOGS SCN and time stamp.