What kinds of database systems are listed on dbdb.io?

dbdb.io (Database of Databases) lists database systems across 14 data models, spanning relational, key-value, document/XML, graph, object-oriented, vector, triplestore/RDF, column family/wide-column, array/matrix, network, multi-value, hierarchical, entity-relationship, and entity-attribute-value systems. Entries include both open-source and proprietary products, from long-established commercial databases to newly created ones. You can browse by data model or track systems through the site's leaderboards.

Coverage by data model

The site organizes its catalog around data models, and each model page shows how many systems it contains. According to the current listing:

Relational systems dominate the catalog by a wide margin, followed by key-value and document/XML. The presence of vector, triplestore/RDF, and array/matrix categories shows the catalog extends well beyond conventional transactional databases into analytical, semantic, and scientific workloads.

Open-source and proprietary systems

The catalog mixes licensing and governance models rather than restricting itself to one. The site maintains dedicated groupings such as Apache Foundation databases (systems controlled by the Apache Software Foundation) and Wisconsin Database Systems (from the University of Wisconsin), alongside individual entries that may be open source or proprietary.

The featured system illustrates the proprietary side: Amazon Redshift, described as a data warehouse product and part of Amazon Web Services, is labeled "Proprietary" and "OLAP," with a start year of 2012.

Established and emerging systems

Listings range from decades-old commercial products to recently created projects. The "Most Viewed" leaderboard over the last 30 days includes Oracle (a multi-model system tagged Key-Value, Graph, Triplestore/RDF, Document/XML, and Relational) and Derby (Relational), while the "Most Recent" leaderboard shows newer or newly modified entries such as OrioleDB, Turso, Xodus, voidDB, and CnosDB.

How the catalog is organized

Two structures make the catalog navigable:

• Browse by Data Model — groups every system under one of the 14 models above, so you can start from the category that matches your workload.
• The Leaderboards — updated daily, with views such as Most Recent (newly modified entries), Most Viewed (last 30 days), and Most Edited (last 30 days). The Most Viewed board also shows percentage change, indicating rising or falling interest.

A Featured System section, updated weekly, highlights one entry in more depth.

What this means for you

If you are looking for a specific class of database — say a vector store, a graph database, or a wide-column system — the data model index is the fastest entry point. If you want to see what is gaining attention or being actively maintained, the leaderboards surface recent activity and viewing trends. Because the catalog includes both open-source and proprietary systems, it works as a starting point for comparison, but you should confirm licensing, pricing, and deployment details on each system's own entry or vendor site.