Java Embedded Database Management Systems

Lightweight, server-free SQL databases that run inside a Java application process — ideal for embedded, edge, and desktop deployments.

Engines

100%

Pure Java

Server Required

Embedded Engines

01HyperSQL (HSQLDB)

A 100% Java relational database engine — small, fast, and multithreaded, with both in-memory and disk-based tables, embedded and server modes. Actively maintained: version 2.7.4 (October 2024) added SQL:2023 features; used in 1,700+ open source projects.

Actively maintained

02H2 Database Engine

A fast, open-source, embeddable Java SQL database with a very small footprint, a browser-based console, and both in-memory and persistent disk-based modes. Widely used for development, automated testing, and lightweight production workloads.

Actively maintained

03Apache Derby

An open-source relational database implemented entirely in Java, with a compact ~3.5MB embedded footprint and a standard embedded JDBC driver. The Apache Derby project was formally retired to a read-only, archival state on 10 October 2025 — no further releases or bug fixes are planned, but the engine and documentation remain available.

Retired / archived

All three engines let you embed a full SQL database directly inside a Java process — no separate database server to install, configure, or operate. HyperSQL and H2 remain under active development;