A. All users except SYS
B. All users except SCOTT
C. All users except sys and SCOTT
D. All users except sys, system, and SCOTT

A. The %ROWTYPE attribute declarations in PL/SQL to access a row will not display the invisible column in the output.
B. The DESCRIBE commands in SQL *Plus will not display the invisible column in the output.
C. Referential integrity constraint cannot be set on the invisible column.
D. The invisible column cannot be made visible and can only be marked as unused.
E. A primary key constraint can be added on the invisible column.

A. The PDB must be open in read only mode.
B. The PDB must be dosed.
C. The unplugged PDB becomes a non-cdb.
D. The unplugged PDB can be plugged into the same multitenant container database (CDB)
E. The unplugged PDB can be plugged into another cdb.
F. The PDB data files are automatically removed from disk.

A. All administration tasks must be done to a specific pluggable database.
B. The pluggable databases increase patching time.
C. The pluggable databases reduce administration effort.
D. The pluggable databases are patched together.
E. Pluggable databases are only used for database consolidation.

A. The import operation must be performed by a user on the target database with the DATAPUMP_IMP_FULL_DATABASE role, and the database link must connect to a user on the source database with the DATAPUMP_EXD_FULL_DATABASE role.
B. All the user-defined tablespaces must be in read-only mode on the source database.
C. The export dump file must be created before starting the import on the target database.
D. The source and target database must be running on the same platform with the same endianness.
E. The path of data files on the target database must be the same as that on the source database.
F. The impdp operation must be performed by the same user that performed the expdp operation.

A. Statistics collection is not done for the CUSTOMERS table when schema stats are gathered.
B. Statistics collection is not done for the CUSTOMERS table when database stats are gathered.
C. Any existing statistics for the CUSTOMERS table are still available to the optimizer at parse time.
D. Statistics gathered on the CUSTOMERS table when schema stats are gathered are stored as pending statistics.
E. Statistics gathered on the CUSTOMERS table when database stats are gathered are stored as pending statistics.

A. Decreasing PCTUSED
B. Decreasing PCTFREE
C. Increasing the number of DBWN process
D. Using Automatic Segment Space Management (ASSM)
E. Increasing db_buffer_cache based on the V$DB_CACHE_ADVICE recommendation

A.2，4，5
B.2，1，4，3，5
C.1，2，3，4，5
D.1，2，4，5

A. Create a SQL Tuning Set (STS) that contains the queries cached in the library cache and run the SQL Tuning Advisor (STA) on the workload captured in the STS.
B. Run the Automatic Workload Repository Monitor (ADDM).
C. Create an STS that contains the queries cached in the library cache and run the SQL Performance Analyzer (SPA) on the workload captured in the STS.
D. Create an STS that contains the queries cached in the library cache and run the SQL Access Advisor on the workload captured in the STS.

A. Execute the query and view Active Session History (ASH) for information about the query.
B. Enable SQL trace for the query.
C. Create a database operation, execute the query, and use the DBMS_SQL_MONITOR. REPORT_SQL_MONITOR function to view the report.
D. Use the DBMS_APPLICATION_INFO.SET_SESSION_LONGOPS procedure to monitor query execution and view the information from the V$SESSION_LONGOPS view.

A. Mount the container database (CDB) and restore the control file from the control file auto backup.
B. Recover and open the CDB in NORMAL mode.
C. Mount the CDB and then recover and open the database, with the RESETLOGS option.
D. Open all the pluggable databases.
E. Recover each pluggable database.
F. Start the database instance in the nomount stage and restore the control file from control file auto backup.