Manage common and local users, roles, privileges and profiles in PDBs

Introduction of Multitenant Architecture

Common users and Local users: This concept came with Oracle Database 12c.

Common Users: a Common user is a user which have the same username and password authentication across PDBs of CDB.

Common users are created at CDB level and the common user can connect to the root and perform operations. By giving proper privileges to common users we can perform operations in PDBs too. Operations can be like granting privileges (more...)

Manage common and local objects in application containers

Introduction of Multitenant Architecture

With Oracle 12c Oracle introduced the concept of common objects which avoids redundancy of metadata and data. Which makes CDB maintenance and up-gradation easy.

Common objects exist in Oracle-supplied schemas and therefore cannot be user-defined.

In the Application container, we can create metadata-linked or data-linked common objects.

There can be following types of common objects we can create with Application Container :

Triggers, tables, object table, object views, stored function, stored (more...)

Backup CDB and PDBs

Introduction of Multitenant Architecture

In this article, we will see how we can take RMAN backup of whole CDB and for the single pluggable database.

To take RMAN backup of the whole CDB we can simply take backup by connecting to target as container database and backup database command.

Let us see by example :

CDB Backup :

Step 1 : Set db_recovery_file_dest and db_recovery_file_dest_size according your database size of whole CDB

SQL> alter system set  (more...)

Export from a Non-CDB and Import in PDB

Introduction of Multitenant Architecture

A logical backup taken from NON-CDB database can be easily imported into a pluggable database without any overhead.

Let us see the example :

Step 1: Check the database status

SQL> select name,open_mode,cdb from v$database;

--------- -------------------- ---


Step 2 : Create the directory

SQL> create directory dir1 as '/u02';

Directory created.


Step 3 : Backup using expdp

[oracle@localhost u02]$ expdp system/oracle@ncdb  (more...)

Changing Instance Parameter in Pluggable Database

Introduction of Multitenant Architecture

As we know in Multi-tenant architecture we have only one instance at container level hence we have only one spfile for Container Database.

So value we set in parameters are associated in CDB$ROOT so applied to cdb root and serve as default parameters for all other containers;

Although we can set some pdb specific value for PDBs where ispdb_modifiable is true.

Let us understand by example.

Check some parameters from v$parameter (more...)