Q21: What is Denormalization and when should it be applied?

Difficulty:MediumTopic:Schema Design

Denormalization intentionally introduces redundant data or pre-aggregated summary columns into a normalized schema.

While normalization optimizes data integrity and write performance, denormalization optimizes read latency in high-scale analytical databases (OLAP) or read-heavy applications by minimizing expensive JOIN operations.

Key Takeaways
  • Denormalization improves read query speeds at the expense of storage space and potential write anomalies.
  • Commonly used in data warehouses, star schema topologies, and read-heavy analytics systems.