Which two statements about Flashback Query are true? (Choose two.)
A.
The database has to be opened with the resetlogs option after performing Flashback Query.
B.
It can be performed to recover ALTER TABLE statements
C.
It fails when undo data pertaining to the transaction is overwritten.
D.
It helps in row-level recovery from user errors.
E.
It is generated by using the redo log files.