Before You Begin

This 15-minute tutorial shows you how to use Database Configuration Assistant (DBCA) to duplicate a container database (CDB).

Background

In Oracle Database 18c, duplicating a CDB requires several commands to be executed.

What Do You Need?

• Oracle Database 19c installed
• A CDB: ORCL with PDB1 in archivelog mode. 
• HR schema installed in PDB1 as an example of application tables. If you want to use the HR.EMPLOYEES table, use the hr.sql. Download the SQL script to the labs directory created on your server /home/oracle/labs. In the script, update the password of the user connected to the database.

Check the Existence of Application Data in the CDB

1. Log in to PDB1 in ORCL as SYSTEM.

   sqlplus system@PDB1
   Enter password: password
   

2. Use the hr.sql script to create the HR user and EMPLOYEES table in PDB1.

   @/home/oracle/labs/hr.sql
   

3. Verify that PDB1 contains the HR.EMPLOYEES table.

   SELECT count(*) FROM hr.employees;
   
   COUNT(*)
   ----------
          107
   

4. Quit the session.

   EXIT

Use DBCA to Duplicate a CDB

In this section, you use DBCA in silent mode to duplicate ORCL as CDB19 .

1. Launch DBCA in silent mode to duplicate ORCL as CDB19. Update the hostname by your server name in the command. SI means Single Instance.

   dbca -silent -createDuplicateDB -gdbName CDB19 -sid CDB19 -primaryDBConnectionString hostname:1521/ORCL -databaseConfigType SI -initParams db_unique_name=CDB19 -sysPassword password -datafileDestination /u02/app/oracle/oradata 
   

   Prepare for db operation 22% complete
   Listener config step 44% complete
   Auxiliary instance creation 67% complete
   RMAN duplicate 89% complete
   Post duplicate database operations 100% complete
   Look at the log file "/u01/app/oracle/cfgtoollogs/dbca/CDB19/CDB19.log" for further details.
   

Check that the CDB Is Duplicated

1. Connect to CDB19 as SYS.

   sqlplus sys@CDB19 AS SYSDBA
   Enter password: password

   SHOW PDBS
   
       CON_ID CON_NAME                       OPEN MODE  RESTRICTED
   ---------- ------------------------------ ---------- ----------
            2 PDB$SEED                       READ ONLY  NO
            3 PDB1                           READ WRITE NO

2. Check that PDB1 contains the HR.EMPLOYEES table as in PDB1 of ORCL.

   CONNECT hr@PDB1
   Enter password: password

   SELECT count(*) FROM employees;
   
     COUNT(*)
   ----------
          107

Use DBCA to Duplicate a CDB with OMF

In this section, you use DBCA in silent mode to duplicate ORCL as CDBOMF19 with OMF files.

1. Launch DBCA in silent mode to duplicate ORCL as CDBOMF19. Update the hostname by your server name in the command.

   dbca -silent -createDuplicateDB -gdbName CDBOMF19 -sid CDBOMF19 -primaryDBConnectionString hostname:1521/ORCL -databaseConfigType SI -initParams db_unique_name=CDBOMF19 -sysPassword password -datafileDestination /u02/app/oracle/oradata –useOMF=TRUE 
   

   Prepare for db operation 22% complete
   Listener config step 44% complete
   Auxiliary instance creation 67% complete
   RMAN duplicate 89% complete
   Post duplicate database operations 100% complete
   Look at the log file "/u01/app/oracle/cfgtoollogs/dbca/CDBOMF19/CDBOMF19.log" for further details.
   

2. Connect to CDBOMF19 as SYS.

   sqlplus sys@CDBOMF19 AS SYSDBA
   Enter password: password

   COL name FORMAT A78
   SELECT name FROM v$datafile;

   NAME
   --------------------------------------------------------------------
   /u02/app/oracle/oradata/CDBOMF19/system01.dbf
   ...
   /u02/app/oracle/oradata/CDBOMF19/PDB1/system01.dbf
   /u02/app/oracle/oradata/CDBOMF19/PDB1/sysaux01.dbf
   /u02/app/oracle/oradata/CDBOMF19/PDB1/undotbs01.dbf
   ...
   

3. Quit the session.
   

   EXIT

Clean Up the CDBs Duplicated

1. Use DBCA to delete CDB19.

   $ORACLE_HOME/bin/dbca -silent -deleteDatabase -sourceDB CDB19 -sid CDB19 -sysPassword password

2. Use DBCA to delete CDBOMF19.

   $ORACLE_HOME/bin/dbca -silent -deleteDatabase -sourceDB CDBOMF19 -sid CDBOMF19 -sysPassword password