053-615

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

　　行迁移必须在表上启用，这表明在闪回表后 rowid 可能会发生变化。如果应用程序依赖 rowid 来获取数据的话，这张表就不能闪回。