guarantee undo retention
add one more redo log group
size the redo log files appropriately
size the UNDO tablespace appropriately
size the SYSTEM tablespace appropriately
configure an appropriate undo retention interval
change automatic undo management to manual
第1题：
A、how long you live here
B、how long have you lived here
C、how long you have lived here
D、how long did you live here
第2题：
You can go out, ____________ you promise to be back before 11 o’clock.
A、as far as
B、as long as
C、as well as
D、as soon as
第3题：
You can go out,()you promise to be back before 12 o'clock.
A. so far as
B. as far as
C. as long as
第4题：
You started a long transaction. Before committing， you executed a query on one of the tables currently being modified. You received the following error： ORA-01555： snapshot too old How would you prevent such an error in the future？（）
第5题：
You can go out, ______you promise to be back before 11 o'clock.
A. even though
B. ever since
C. as far as
D. as long is
7．答案为D 你可以出去，只要你保证11点之前回来。even though“即使”；ever since“自从”；as far as“就……而言”；as long as“只要”。根据句子的逻辑关系，只有D选项正确。
第6题：
You will get the message ______.
A、not long after
B、not long
C、before long
D、long before
第7题：
A、how long have you lived here
B、how long you lived here
C、how long you have lived here
D、you have lived here how long
第8题：
A、all the same
B、in the end
C、after all
D、before long
第9题：
Before CPR is started，you should ______．
A.Establish an open airway
B.Treat any bleeding wounds
C.Insure the victim is conscious
D.Make the victim comfortable
第10题：
You work as a database administrator for Supportcenter.cn. In your production database， the size of Database Buffer Cache needs to be increased immediately for the current as well as future instances of the database. The Oracle instance has been configured to accommodate any changes in the size of the memory structures. At this is production database， you want to accomplish this task with no impact on the user’s connections. Which activity must you have completed before accomplishing this task？（）