多项选择题 Which three statements are true about the working of system privileges in a multitenant control database(CDB) that has pluggable databases (PDBs)?（）

多项选择题 Examine the commands executed to monitor database operations: $> conn sys oracle/oracle@prod as sysdba SQL > VAR eid NUMBER SQL > EXEC: eid := DBMS_SQL_MONITOR.BEGIN_OPERATION (‘batch_job’ , FORCED_TRACKING => ‘Y’); Which two statements are true?（）

单项选择题 Flashback is enabled for your multitenant container database (CDB), which contains two pluggable database (PDBs). A local user was accidently dropped from one of the PDBs. You want to flash back the PDB to the time before the local user was dropped. You connect to the CDB and execute the following commands: SQL > SHUTDOWN IMMEDIATE SQL > STARTUP MOUNT SQL > FLASHBACK DATABASE to TIME “TO_DATE (‘08/20/12’ , ‘MM/DD/YY’)”; Examine following commands: 1. ALTER PLUGGABLE DATABASE ALL OPEN; 2. ALTER DATABASE OPEN; 3. ALTER DATABASE OPEN RESETLOGS; Which command or commands should you execute next to allow updates to the flashback back schema?（）