About PeekDB

PeekDB is a knowledge base dedicated to understanding how databases work under the hood. We peer into the internals of PostgreSQL, MySQL, SQLite, and other data systems — explaining storage engines, query planners, concurrency control, indexing strategies, and distributed consensus.

Why PeekDB Exists

Most database documentation tells you what a feature does. Academic papers tell you why a design decision was made. But there's a gap: understanding how it actually works in the source code, and what happens on disk and in memory when a query runs.

PeekDB fills that gap with annotated source code analysis, visual explanations of algorithms, and practical benchmarks.

Content License

All content on PeekDB is licensed under Creative Commons Attribution 4.0 (CC BY 4.0). You are free to share and adapt the material, as long as you give appropriate credit.