In what cases can excessive normalization of a database negatively affect its performance?

Over-normalization of a database can negatively impact performance in the following cases:

• Excessive number of joins (JOINs): When highly normalized, data is split into many tables, leading to the need to perform numerous JOIN queries to retrieve complete information. This increases query execution time.

• Increased query complexity: Complex queries involving many tables are harder to optimize, which can lead to reduced speed.

• Caching issues: Dividing data into many tables makes effective caching difficult, as data is scattered.

• Increased system load during read operations: If the database is oriented towards frequent reads, over-normalization can slow down operations because data must be assembled from different tables.

Ultimately, over-normalization is justified if data integrity and minimization of redundancy are important, but for systems with high read performance requirements, denormalization or balancing normalization with performance is often used.