[单选]

Your multitenant container database (CDB) contains a pluggable database, HR_PDB. The default permanent tablespace in HR_PDB is USERDATA. The container database (CDB) is open and you connect RMAN.
You want to issue the following RMAN command:
RMAN > BACKUP TABLESPACE hr_pdb:userdata;
Which task should you perform before issuing the command?（）

专利权 反思小说大多为中篇，请简要说明原因。 A user complains that he gets the following error message repeatedly after executing some SQL statements.The error message forces the user to log off from and log onto the database to continue his work.  ORA-02392：exceeded session limit on CPU usage，you are being logged off Which action would you take to increase the session limit on CPU usage？（） Modify the profile assigned to the user.。 Modify the roles assigned to the users.。 Modify the object privileges assigned to the user.。 Modify the system privileges assigned to the users.。 Modify the value for the RESOURCE_LIMIT parameter in the parameter file.。 You have been assigned to manage a set of databases. The previous DBA did not leave you notes regarding the structure of each of the databases. While analyzing an instance， you notice that the system identifier （SID） for the instance is set to ’+ASM’. What is the purpose of this instance？（）  This instance is being used to manage the operating system files.。  This instance is being used to manage the files of other databases.。  This instance is being used to manage the instances of other databases.。  This instance is being used to manage the background processes of other instances.。 壁挂空调不能安装在（）。 墙壁。 门口。 设备顶部。 门上。

Your multitenant container database (CDB) contains a pluggable database, HR_PDB. The default permanent tablespace in HR_PDB is USERDATA. The container database (CDB) is open and you connect RMAN.
You want to issue the following RMAN command:
RMAN > BACKUP TABLESPACE hr_pdb:userdata;
Which task should you perform before issuing the command?（）