Fluree DB vs QLever

Fluree DB is a graph database for data that needs queryable history, verifiable transactions, and fine-grained access rules. It stores RDF triples and appends each cryptographically signed transaction to an immutable ledger, preserving a full temporal history. Graph data can be queried alongside full-text and vector search, with time-travel queries available. Attribute-, role-, and relationship-based policies are evaluated at query time down to individual triples. Fluree is built on W3C standards including JSON-LD, RDF, SPARQL, OWL, and SHACL; listed capabilities include SPARQL 1.1, reasoning, RDF-star, and federated queries. Interfaces include FlureeQL and REST, plus MCP server configuration, LangChain, and LlamaIndex options. Official SDKs are listed for JavaScript/TypeScript, Python, and Java. It runs as a static binary without a JVM or external dependencies, with Docker, Homebrew, shell, PowerShell, and source-build options. The Open Source and Fluree AI plans are free. The Business Source License 1.1 applies, and commercial licensing is available by contacting Fluree.

QLever is an open-source graph database for loading and querying large RDF datasets. It implements SPARQL 1.1, including federated queries, named graphs, the Graph Store HTTP Protocol, and updates. The project says it can handle more than a trillion triples on a single commodity machine. It also provides text search over knowledge bases, context-sensitive SPARQL autocompletion, live query analysis, and spatial queries with interactive maps of large sets of geometric objects. QLever can run embedded inside C++ code without a client-server setup. Example datasets include Wikidata, Wikimedia Commons, OpenStreetMap, UniProt, PubChem, and DBLP. It is self-hosted, with official packages for Debian, Ubuntu, Ubuntu-derived distributions, and macOS, plus Docker and Podman images. The official Homebrew package supports ARM64 Apple Silicon Macs, not Intel Macs. Windows use runs Docker inside a virtual machine and may incur significant performance and RAM costs; binary releases are in progress. QLever is free under the Apache 2.0 license.