Which two statements regarding the result of the query shown in the Exhibit are correct? (Choose two.)
A.
The LAST_SCN value in the first row is NULL which means that version of the row still exists at SCN 6636300
B.
The LAST_SCN value in the second row is NULL which means that version of the row still exists at SCN 6636300
C.
The LAST_SCN value in the second row is NULL which means that version of the row no longer exists because it was deleted
D.
The LAST_SCN value in the third row is 6636280 which means that version of the row exists above SCN 6636280
Explanation:
VERSIONS_STARTSCN or VERSIONS_STARTTIME
Starting SCN and TIMESTAMP when row took on this value. The value of NULL is returned if the row was created before the lower bound SCN or TIMESTAMP.
VERSIONS_ENDSCN or VERSIONS_ENDTIME
Ending SCN and TIMESTAMP when row last contained this value. The value of NULL is returned if the value of the row is still current at the upper bound SCN ot
TIMESTAMP.
VERSIONS_XID – ID of the transaction that created the row in it’s current state. VERSIONS_OPERATION – Operation performed by the transaction ((I)nsert, ( U)pdate or (D)elete)
REF.: Metalink Note:270270.1 – Flashback Version Query & Flashback Transaction Query – Oracle 10G Enhancement