The IT industry has increasing developed server technology with increased levels of memory and processing power which have out grown traditional system setups of one application to one server.  Most modern physical servers are very capable of handling multiple applications and even multiple server platforms through Virtualization technologies.   This is just as true with RDBMS suites.   Oracle has developed Multitenant architecture databases to take advantage of excess server power and reduce the physical hardware foot print.   This technology is known as CDB – Container Databases and PDB – Pluggable Databases.

Container Databases (CDB) act as the container where you store all of your application and system databases.  It contains and manages all of the initialization parameters, memory resources, processor resource and shared services granted to the RDBMS by the OS and created through the RDBMS.   Container Databases should not be used by application data stores to process user requests or perform any action for an outside application.   It should only be used to house PDB data stores which do provide data storage and manipulations of applications.  CDB’s can hold one to many PDBs.

Pluggable Databases (PDB) act as the application data stores and perform all actions that a traditional Oracle database perform through the use of resources granted by the CDB.   It allows us to reduce the overhead of managing multiple Oracle RDBMS Suites and increase the utilization of current hardware resources.  PDB’s are housed in a single CDB and can be moved from one CDB to another CDB.

Larry Catt

OCP