615.Before a Flashback Table operation, you execute the following command:
ALTER TABLE employees ENABLE ROW MOVEMENT;
Why would you need this to be executed?
A. Because row IDs may change during the flashback operation
B. Because the object number changes after the flashback operation
C. Because the rows are retrieved from the recycle bin during the flashback operation
D. Because the table is moved forward and back to a temporary during the flashback opertion
Answer: A
答案解析：
参考：http://docs.oracle.com/cd/E11882_01/server.112/e10897/backrest.htm#ADMQS12236
Before you can use Flashback Table, you must ensure that row movement is enabled on the table to be flashed back, or returned to a previous state. Row movement indicates that rowids will change after the flashback occurs. This restriction exists because if rowids before the flashback were stored by an application, then there is no guarantee that the rowids will correspond to the same rows after the flashback.