Performance Tuning, Denormalisation, Scaling, and Best Practices
Learn how to improve DBMS performance in practical systems through indexing, query tuning, workload awareness, scaling strategies, and disciplined database engineering.
Inside this chapter
- Performance Problems in Real Databases
- Common Tuning Techniques
- Denormalisation and Materialization
- Vertical and Horizontal Scaling
- Operational Best Practices
- Production Example
Series navigation
Study the chapters in order for the clearest path from database fundamentals and SQL to transactions, indexing, recovery, distributed systems, tuning, and advanced DBMS engineering understanding. Use the navigation at the bottom to move smoothly across the full tutorial series.
Performance Problems in Real Databases
Slow queries, lock contention, poor indexing, large table scans, weak schema choices, noisy background jobs, excessive writes, and misused transactions can all create production pain. Database tuning is therefore a practical engineering skill.
Common Tuning Techniques
- Add or improve indexes based on actual query patterns
- Reduce unnecessary row and column retrieval
- Rewrite inefficient joins or nested subqueries
- Use batching where appropriate
- Review transaction scope and lock duration
Denormalisation and Materialization
Sometimes extra redundancy is introduced intentionally for speed, such as summary tables, precomputed reports, or materialized views. This should be done carefully because it trades update simplicity for read performance.
Vertical and Horizontal Scaling
Vertical scaling means using bigger hardware. Horizontal scaling means distributing load or data across multiple systems. The right approach depends on workload, budget, data consistency needs, and operational maturity.
Operational Best Practices
- Measure before tuning blindly
- Keep schema changes controlled and reviewed
- Test backup and restore, not only backup creation
- Separate OLTP and analytics workloads when necessary
- Document ownership, access, and query expectations
Production Example
A learning platform with millions of video progress records may need better indexing, partitioning, query reshaping, and summary tables to keep dashboards fast. Performance tuning here directly affects user experience and infrastructure cost.