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正确答案：BD
闪回数据归档请参考：http://blog.csdn.net/guoyjoe/article/details/9199963
直接用实验解析答案
答案A，不开归档才也可以用Flashbackup Data Archive闪回数据归档，闪回数据归档与UNDO有关，与ARCHIVE LOG无关。
在没有归档下也可以创建闪回数据归档，操作如下：
（1）关闭归档
gyj@OCM> conn / as sysdba
Connected.
sys@OCM> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
sys@OCM> startup mount;
ORACLE instance started. Total System Global Area 839282688 bytes
Fixed Size 2233000 bytes
Variable Size 436211032 bytes
Database Buffers 394264576 bytes
Redo Buffers 6574080 bytes
Database mounted.
sys@OCM> alter database noarchivelog; Database altered. sys@OCM> alter database open; Database altered. sys@OCM> archive log list;
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination /arch
Oldest online log sequence 97
Current log sequence 99
（2）创建闪回数据归档
sys@OCM> conn gyj/gyj
Connected.
gyj@OCM> create flashback archive flash1 tablespace gyj quota 10M retention 1 year; Flashback archive created.
说明没开归档下也可以创建闪回数据归档，所以A答案错。
答案B正确，只有在自动管理undo表空间才能创建闪回数据归档。
（1） UNDO自动管理
sys@OCM> conn gyj/gyj
Connected.
gyj@OCM> drop flashback archive flash1; Flashback archive dropped. gyj@OCM> show parameter undo NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string AUTO
undo_retention integer 900
undo_tablespace string UNDOTBS1
（2） 创建闪回数据归档，成功
gyj@OCM> create flashback archive flash1 tablespace gyj quota 10M retention 1 year; Flashback archive created.
（3） UNDO手动管理
gyj@OCM> alter system set undo_management=manual scope=spfile; System altered. gyj@OCM> shutdown immediate;
ORA-01031: insufficient privileges
gyj@OCM> conn / as sysdba
Connected.
sys@OCM> startup force;
ORACLE instance started. Total System Global Area 839282688 bytes
Fixed Size 2233000 bytes
Variable Size 436211032 bytes
Database Buffers 394264576 bytes
Redo Buffers 6574080 bytes
Database mounted.
Database opened.
sys@OCM> show parameter undo NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string MANUAL
undo_retention integer 900
undo_tablespace string UNDOTBS1
（4） 创建闪回数据归档，失败。
sys@OCM> createflashback archive flash2 tablespace tp1 quota 10M retention 1 year;
create flashbackarchive flash2 tablespace tp1 quota 10Mretention 1 year
*
ERROR at line 1:
ORA-55628: Flashback Archive supports Oracle 11g orhigher
所以答案B正确只有在自动管理的UNDO表空间下才能创建闪回数据归档
答案C，不正确，不需要设Undo retention为guarantee，默认Undo retention为 no guarantee就可以创建闪回数据归档，答AB都在no guarante下创建的闪回数据归档，能过如下视图查是不是NO GUARANTEE,看UNDOTBS1表空间是NOGUARANTEE
sys@OCM> SELECT TABLESPACE_NAME,RETENTION FROM DBA_TABLESPACES; TABLESPACE_NAME RETENTION
------------------------------ -----------
SYSTEM NOT APPLY
SYSAUX NOT APPLY
UNDOTBS1 NOGUARANTEE
TEMP NOT APPLY
USERS NOT APPLY
EXAMPLE NOT APPLY
GYJ NOT APPLY
TP1 NOT APPLY
MRKT NOT APPLY
TEMP1 NOT APPLY
TEMP4 NOT APPLY
答案D正确，表空间必须是ASSM才能创建闪回数据归档。上例是建在表空间TP1上是AUTO管理段的。
sys@OCM> SELECT TABLESPACE_NAME,SEGMENT_SPACE_MANAGEMENT FROM DBA_TABLESPACES; TABLESPACE_NAME SEGMEN
------------------------------ ------
SYSTEM MANUAL
SYSAUX AUTO
UNDOTBS1 MANUAL
TEMP MANUAL
USERS AUTO
EXAMPLE AUTO
GYJ AUTO
TP1 AUTO
MRKT AUTO
TEMP1 MANUAL
TEMP4 MANUAL
举个反例，我建个MSSM的表空间，看能不能创闪回数据归档：
sys@OCM> create tablespace tp2 datafile '/u01/app/oracle/oradata/ocm/tp2.dbf' size 100M Segment Space Management MANUAL; Tablespace created. sys@OCM> create flashback archive flash3 tablespace tp2 quota 10M retention 1 year;
create flashback archive flash3 tablespace tp2 quota 10M retention 1 year
*
ERROR at line 1:
ORA-55627: Flashback Archive tablespace must be ASSM tablespace
看到提示了吧，必须要用ASSM表空间。
所以说啊,学习OCP一定要一道道题认认真真做实验，操作->查资料->思考->总结（反复折腾才能真正才为大师啊，这需要时间，慢慢累积，成为高手只是时间问题。），不希望大家是Paper OCP!
大家有在学习OCP或在Oracle入门时找不到方向的可以找我。