Dydra vs RDFox

Dydra is a cloud graph database for highly connected data, including social networks. It stores information as a property graph and supports SPARQL 1.1 queries and updates through a standard endpoint for each repository. Repositories import RDFa, RDF/JSON, N-Quads, N-Triples, RDF/XML, TriG and Turtle, and export N-Triples, Turtle and RDF/XML. Dydra also provides a standard REST API and a Ruby client gem that can operate as a command-line interface. The service says it manages versioning, disaster recovery and performance for the data store. Described applications include social networking, movie relationships and transaction logs. A free Basic use plan has limited resources: public evaluation accounts allow five queries per second and repositories should remain at or below one million statements. Federation is disabled for public accounts, and the default graph is fixed to the repository default. Customers retain data ownership and may delete data. Dydra is headquartered in Berlin, Germany.

RDFox is a main-memory data store for centralized RDF graphs, queried with SPARQL 1.1. It represents rules and ontological axioms with Datalog, OWL 2 and SWRL, and updates rule consequences as data changes; it can process 2–3 million new-fact inferences per second. Its supported knowledge-graph technologies include RDF, SPARQL 1.1, Datalog, SWRL, OWL 2 RL and SHACL. Java applications can connect through a native API, or RDFox can run as a standalone server through a REST API. Import and export formats include CSV, JSON, N-Triples, Turtle, TriG and OWL 2 Functional-Style Syntax. It can replicate knowledge and data changes across servers to maintain service during an outage, and deployments are described for cloud, on-premises, on-device and edge use. RDFox runs on Linux, macOS and Windows. Security features include encryption at rest, mutual-TLS client-certificate authentication and OpenID Connect single sign-on. Pricing is on request; the free 30-day evaluation license is restricted to evaluation and non-commercial use.