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单选题
Which statement is true regarding Flashback Version Query?()
A

 It returns versions of rows only within a transaction.

B

 It can be used in subqueries contained only in a SELECT statement.

C

 It will return an error if the undo retention time is less than the lower bound time or SCN specified.

D

 It retrieves all versions including the deleted as well as subsequently reinserted versions of the rows.


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