单项选择题
A.The backup contains all the used blocks.
B.The backup contains all the used and unused blocks.
C.The backup contains blocks that have changed since the last level 0 backup.
D.The backup contains blocks that have changed since the last level 1 backup taken last week.
多项选择题 You perform differential incremental level 1 backups of your database on each working day and level 0 backup on Sundays， to tape. Which two statements are true about differential incremental backups（）
多项选择题 You are working on a database that must be functioning 24 hours a day， 7 days a week. The databaseis configured in ARCHIVELOG mode. Which two options do you have for performing user-managed backups（）
多项选择题 You are managing an Oracle Database 11g database. The database is open， and you plan to performRecovery Manager （RMAN） backups. Which three statements are true about these backups（）