What are the key features of Oracle Multitenant Architecture?

Oracle Multitenant Architecture is a feature introduced in Oracle Database 12c that allows you to manage multiple pluggable databases (PDBs) within a single container database (CDB). Here are the key features of Oracle Multitenant Architecture:

  1. Container Database (CDB):
    • The CDB is the main database instance that hosts multiple pluggable databases (PDBs). It contains system-related metadata and provides common services and resources to all the PDBs within it.
    • The CDB includes the Oracle supplied data dictionary and metadata specific to the entire container database.
  2. Pluggable Databases (PDBs):
    • PDBs are individual, fully functional databases that reside within a CDB. Each PDB has its own set of data files, tablespaces, users, and configuration settings.
    • PDBs are essentially self-contained, allowing for easy provisioning, cloning, and management.
  3. Application Containers:
    • Application Containers are introduced in Oracle Database 12.2 as a further extension of the Multitenant Architecture. They allow grouping of PDBs that share the same application or schema.
    • Each Application Container can contain multiple PDBs and provides a way to isolate different applications or schemas within the same CDB.
  4. Resource Management:
    • Resource management in Oracle Multitenant Architecture allows you to allocate and manage system resources such as CPU, memory, and I/O among the different PDBs within a CDB.
    • This ensures that each PDB gets its fair share of resources and prevents one PDB from monopolizing resources at the expense of others.
  5. Data Isolation and Security:
    • Each PDB operates independently of other PDBs within the same CDB, providing data isolation and security.
    • PDBs have their own sets of users, roles, and privileges, allowing for granular control over access to data and resources.
  6. Patch and Upgrade Simplification:
    • Oracle Multitenant Architecture simplifies the patching and upgrading process by allowing you to patch or upgrade the entire CDB, including all PDBs, in a single operation.
    • This reduces downtime and administrative overhead compared to patching or upgrading individual non-CDB databases.
  7. Backup and Recovery Efficiency:
    • Backup and recovery operations in Oracle Multitenant Architecture can be performed at both the CDB and PDB levels.
    • You can back up and recover individual PDBs independently of each other, providing flexibility and efficiency in managing data protection.
  8. Reduced Overhead:
    • Oracle Multitenant Architecture reduces overhead by consolidating multiple databases into a single CDB, thereby reducing the number of database instances and administrative tasks required.
    • This consolidation can lead to cost savings in terms of hardware, licensing, and administrative resources.

Oracle Multitenant Architecture provides a scalable, efficient, and cost-effective solution for managing multiple databases within a single Oracle Database instance. It simplifies administration, improves resource utilization, and enhances security and isolation between different database environments.