单项选择题
A.It records usernames and passwords of users when granted the DBA role.
B.It contains usernames and passwords of users for whom auditing is enabled.
C.It is used by Oracle to authenticate users for remote database administration.
D.It records usernames and passwords of all users when they are added to OSDBA or OSOPER operating system groups.
多项选择题 Your database instance is running with full workload after database creation. You have decided to useafixed-sizeundo tablespace. You want to use the Undo Advisor to estimate the capacity of the undotablespace. Which two factors must you consider before using the Undo Advisor to estimate the capacity of the undotablespace（）
单项选择题 WhichstatementistrueabouttheUNDO_RETENTIONparameterwhenretentionguaranteeisnotenabled（）
单项选择题 InwhichsituationmaytheUNDO_RETENTIONparameterbeignored，evenifitissettoavalue（）