While planning to manage more than one database in your system， you perform the following activities： 
1. Organize different categories of files into independent subdirectories. 
2. Use consistent naming convention for database files. 
3. Separate administrative information pertaining to each database. 
Which option corresponds to the type of activities performed by you？（）

多项选择题Whichtwostatementsaretrueaboutsimpleviews？（）

A.Views can be created as read only.
B.Views are data segments like tables.
C.Views can be created on the basis of more than one table.
D.Data manipulation language （DML） operations cannot be performed on views.

单项选择题YouwanttheuserAPP_DBAtoadministertheOracledatabasefromaremotemachine.APP_DBAisgrantedtheSYSDBAprivilegetoperformadministrativetasksonthedatabase.WhichfileisusedbytheOracledatabaseservertoauthenticateAPP_DBA？（）

A.control file
B.password file
C.listener controller file
D.control file and password file

多项选择题WhichtwostatementsaretrueabouttherolesintheOracledatabase？（）

A.A role can be granted to itself.
B.Roles are owned by the SYS user.
C.Roles can be granted to other roles.
D.A role cannot be assigned external authentication.
E.A role can contain both system and object privileges.

单项选择题Youareworkingonanonlinetransactionprocessing（OLTP）system.YounoticethataPL SQLproceduregotexecutedtwiceat2）00p.m.ThishasincorrectlyupdatedtheEMP_SALtable.Howwouldyourevertthetabletoitsstateat2）00p.m.？（）

A.Perform point-in-time recovery to 2： 00 p.m.
B.Use Flashback Table feature to revert the changes.
C.Restore the entire database from the recent backup and open it.
D.Issue the rollback statement with system change number （SCN）.

单项选择题YourtestdatabaseisrunninginNOARCHIVELOGmode.Whataretheimplicationsofthis？（）

A.You can perform open database backups.
B.You can perform closed database backups.
C.You cannot perform schema-level logical backups.
D.You can perform the backup of only the SYSTEM tablespace when the database is open.