Application container is a new feature introduced in Oracle 12c Release 2. The main benefit of an application container in your environment is it makes application level patching and upgrade easy.
In a product based company where you have multiple customers which are having same application running in your PDBs. We can take benefits of application container where we providing SaaS [Software as a Service] service.
Now let us understand each term :
- Application Container: Application container is PDB which we create with AS APPLICATION CONTAINER clause. It stores data and metadata for one or more application task. A master application definition is a maintainer in the application container.
- Application Root: Application root is a container inside cdb$root container. For each PDB created with AS APPLICATION CONTAINER, Oracle creates an application root. Application root contains descriptions of Oracle-supplied common objects which are shared by Application PDBs.
- Application Seed: Application seed is a PDB created inside Application Root. That helps us to create application PDBs quickly.
- Application PDB: It is a pluggable database which we create after setting an application container as a current container.
Each application pdb can be a part of only one application container. Changes made to the Application Container requires synchronization with all application pdbs.
Below image gives a brief idea of how application container works :
In the above diagram, we can see under CDB$ROOT container 4 PDB exists. pdb seed,pdb1 and two application container.app_order application container has two pdbs ord_mob and ord_com. ord_mob and ord_com stores the same application data.
app_sales application container has two pdbs sal_mob and sal_com. These two containers store the same application data.
Characteristics of Application Container :
Application common objects exist only in Application Root. Metadata or data stored in Application root are only accessible in Application PDBs associated with that application container.
One can instantly create application pdb under application container by creating a clone of application seed pdb or by unplugging and plugging, cloning remote and local pdbs to join application container.
Stay tuned for More articles on Oracle Multitenant
Thank you for giving your valuable time to read the above information.
If you want to be updated with all our articles send us the Invitation or Follow us:
Telegram Channel: https://t.me/helporacle
Skant Gupta’s LinkedIn: www.linkedin.com/in/skantali/
Joel Perez’s LinkedIn: Joel Perez’s Profile
LinkedIn Group: Oracle Cloud DBAAS
Facebook Page: OracleHelp