DB2

Database 2

Enhanced Definition

IBM's enterprise-class relational database management system for z/OS, supporting SQL and providing scalable, secure data management for mission-critical applications. DB2 is the primary RDBMS on mainframe platforms.

Key Characteristics

- Full SQL standard compliance
- ACID transaction support
- High availability and disaster recovery
- Parallel query processing
- Advanced security and auditing
DB2 Architecture:
- DB2 Subsystem: Core database engine
- Buffer Pools: Memory caching for data and indexes
- Log Files: Transaction logging for recovery
- Catalog: System tables containing metadata
- Storage Groups: Managing DASD allocations
DB2 Components:
- Database: Collection of related tables
- Table Space: Physical storage for tables
- Tables: Row and column data structures
- Indexes: Access paths for efficient retrieval
- Views: Virtual tables derived from base tables
- Stored Procedures: Server-side program logic
- User-Defined Functions: Custom SQL functions
- Triggers: Automatic event-driven actions
SQL Capabilities:
- Data Definition Language (DDL)
- Data Manipulation Language (DML)
- Data Control Language (DCL)
- Advanced query features (joins, subqueries, unions)
- Window functions and analytics
- XML and JSON support
Performance Features:
- Query optimization and execution plans
- Multi-row fetch and insert
- Parallel processing (query parallelism)
- Data sharing across Sysplex
- In-memory database acceleration
- Query workload management

Use Cases

- Enterprise data warehousing
- Online transaction processing (OLTP)
- Customer relationship management (CRM)
- Financial transaction processing
- Business intelligence and analytics