Your database instance is running with full workload after database creation. You have decided to us

Your database instance is running with full workload after database creation. You have decided

to use a fixed-size undo tablespace. You want to use the Undo Advisor to estimate the capacity of

the undo tablespace. Which two factors must you consider before using the Undo Advisor to

estimate the capacity of the undo tablespace? (Choose two.)

选项

A.the retention period to support flashback

B.the expected length of the longest-running query

C.the number of undo tablespaces in the database

D.the size of the Flash Recovery Area for the database instance

Correct Answers: A B

想把undo表空间设置成固定大小,需要考虑哪些方面?

A: 正确,支持的闪回时间长短.

B: 正确,支持的最长时间查询

C: 错误,undo的大小设置,不需要考虑数据库有几个undo表空间.

D: 错误,undo的大小设置,跟快速恢复区大小没关系.