Databases

Summary: Specialized data systems optimized for storing, retrieving, and manipulating data.

Sources: chapter1, chapter12

Last updated: 2026-04-18


The word “database” is a broad term encompassing many different types of systems, each optimized for different workloads and data models.

Evolution

  • Relational Databases (SQL): Structured data with strong transactional guarantees (source: chapter2).
  • NoSQL Databases: Scalable, flexible data stores for unstructured or semi-structured data (source: chapter2).
  • Distributed Databases: Systems that distribute data and processing across multiple nodes (source: chapter5).

Unbundling

In recent years, the trend has been toward “unbundling” database functions into specialized, composed services like message brokers, caches, and stream processors (source: chapter12).