Oracle has introduced new Multitenant Option from Oracle 12cR1 and this option enables an Oracle database to function as a container database(CDB). A CDB includes zero, one, or many pluggable databases. A PDB is a portable collection of schemas, schema objects, and nonschema objects that appears to an Oracle Net client as a non-CDB. All Oracle databases before Oracle Database 12c were non-CDBs.
Refer here for more details on Oracle Multitenant option.
In this article I will demonstrate an overview of creating a CDB and PDB database using DBCA.
Refer here to Create Container database (CDB) in silent mode
Here I am using VNC viewer for database creation in graphical mode. Refer the link to Install and configure VNC Server on Linux 7
Create CDB using DBCA
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Select Create a database and click next
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Select Advanced Configuration
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Select Oracle Single instance database, leave the template section with default one selected and click on Next
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Provide the details as per your requirement,
Global database name:
SID:
Select Create as Container datbase
Number of PDBs:
PDB Name:
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Provide the Datafile storage type as per your environment
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Specify the Recovery files storage type, Flash Recover Area and Size and click Next
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Select the listener if already have one or Create a new one as below
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Choose Automatic memory management and provide the Memory Target Size,
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Provide the processes Count
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Choose the Character set and click on Next
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Select Configure Enterprise management option and provide the EM express port. If EM cloud control is in place, provided the details. Then click on Next
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Provide the Password and click on Next
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Select Create database and click next
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Verify the parameters and click on Finish to start the DB creation.
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Database has been successfully created, click on close
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Connect to database and verify,
[oracle@cdb12c /]$ . oraenv
ORACLE_SID = [cdbdev] ?
The Oracle base remains unchanged with value /u01/app/oracle
[oracle@cdb12c /]$
[oracle@cdb12c /]$ sqlplus "/as sysdba"
SQL*Plus: Release 12.2.0.1.0 Production on Sun Jan 17 20:47:35 2021
Copyright (c) 1982, 2016, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> select name, open_mode, cdb from v$database;
NAME OPEN_MODE CDB
--------- -------------------- ---
CDBDEV READ WRITE YES
SQL>
Check the PDB stauts
SQL> col name for a15
SQL> select name, open_mode from v$pdbs;
NAME OPEN_MODE
--------------- ----------
PDB$SEED READ ONLY
PDB1 READ WRITE
SQL> select name, pdb, network_name from v$services;
NAME PDB NETWORK_NAME
-------------------- --------------- -------------------------
pdb1.localdomain PDB1 pdb1.localdomain
SYS$BACKGROUND CDB$ROOT
SYS$USERS CDB$ROOT
cdbdevXDB CDB$ROOT cdbdevXDB
cdbdev.localdomain CDB$ROOT cdbdev.localdomain
SQL>
Container database CDBDEV and Pluggable database PDB1 created successfully.
Hope this helps…