36、
36.In which situation may the UNDO_RETENTION parameter be ignored, even if it is set to a value? A. When the data file of the undo tablespace is autoextensible B. When there are more than one undo tablespace available in the database C. When the undo tablespace is of a fixed size and retention guarantee is not enabled D. When the undo tablespace is autoextensible and retention guarantee is not enabled Answer: C
在固定大小的还原表空间,且没有设置retention guarantee 强制保留,UNDO_RETENTION 就会被忽略
37、
37.You perform differential incremental level 1 backups of your database on each working day and level 0 backup on Sunday to tape: Which two statements are true about differential incremental backups? (Choose two.) A. The backup performed on Sundays contains all the blocks that have ever been used in the database B. The backup performed on Sundays contains all the blocks that have changed since the last level 1 backup C. The backup performed on each working day contains all the blocks that have changed since the last level 0 backup D. The backup performed on Monday contains all the blocks that have changed since the level 0 backup and every other working day contains all the blocks that have changed since the level 1 backup Answer: AD
增量备份
38、
38.Your database is open and the LISTENER listener is running. The new DBA of the system stops the listener by using the command: LSNRCTL> STOP What happens to the sessions that are presently connected to the database instance? A. The sessions are able to perform only queries B. The sessions are not affected and continue to function normally C. The sessions are terminated and the active transactions are rolled back D. The sessions are not allowed to perform any operations till the listener is started Answer: B
当会话连接到数据库后,即使是停止了监听,也不影响会话的正常操作的。
39、
39.You are managing an Oracle Database 11g database with the following backup strategy: 1. On Sunday, an incremental level 0 tape backup is performed 2. Monday through Saturday, a cumulative incremental level 1 tape backup is performed Which two statements are true regarding the backups performed? (Choose two.) A. The backup performed in step 1 backs up all blocks that have ever been in use in the database B. The backup performed in step 2 copies all the blocks changed since the most recent level 0 backup C. The backup performed in step 1 backs up all the blocks changed since the most recent level 1 backup D. The backup performed in step 2 backs up all blocks that have changed since the most recent incremental backup at level 1 Answer: AB
备份策略
40、View the Exhibit and examine the attributes of an undo tablespace.
In an OLTP system, the user SCOTT has started a query on a large table in the peak transactional hour that performs bulk inserts. The query runs for more than 15 minutes and then SCOTT receives the following error: ORA-01555: snapshot too old What could be the reason for this error? A. The query is unable to get a read-consistent image. B. There is not enough space in Flash Recovery Area. C. There is not enough free space in the flashback archive. D. The query is unable to place data blocks in undo tablespace. Answer: A
快照太旧 错误是因为没有足够的还原数据来实现读取一致性