053(七十七）

381、

381.Which pseudo column could you use to identify a unique row in a Flashback Versions Query?
A. XID
B. VERSIONS_PK
C. VERSIONS_XID
D. VERSIONS_UNIQUE

382、

382.Which of the following can be used in conjunction with a Flashback Versions Query to filter the results? (Choose all that apply.)
A. A range of SCN values
B. A list of SCN values
C. A starting and ending timestamp
D. Minimum and maximum sequence values
E. A list of sequence values

383、

383.At the request of a user, you issue the following command to restore a dropped table:
flashback table "BIN$F2JFfMq8Q5unbC0ceE9eJg==$0" to before drop;
Later, the user notifies you that the data in the table seems to be very old and out of date.
What might be the problem?
A. Because a proper range of SCNs was not specified, the wrong data was restored.
B. A proper range of timestamps was not specified, so the wrong data was restored.
C. A previous Flashback Drop operation had been performed, resulting in multiple versions of the table being stored in the Recycle Bin.
D. Either option A or B could be correct. Not enough information was provided to determine which.
E. None of the above.

384、

384.Which of the following statements is true regarding the VERSIONS BETWEEN clause?
A. The VERSIONS BETWEEN clause may be used in DML statements.
B. The VERSIONS BETWEEN clause may be used in DDL statements.
C. The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.
D. The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.

385、

385.Which of the following statements is true regarding implementing a Flashback Table recovery?
A. An SCN is never used to perform a Flashback Table recovery.
B. If a significant number of changes have been made to the table, row movement must be enabled.
C. The tablespace must be offline before performing a Flashback Table recovery.
D. Flashback Table recovery is completely dependent on the availability of undo data in the undo tablespace.