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:
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.