Ontop vs Stardog
Both are rdf databases queried with SPARQL. Ontop (2009, Apache-2.0, Java) ranks #19 this month; Stardog (2011, Proprietary, Java) ranks #20.
| Attribute |  Ontop |  Stardog |
|---|---|---|
| At a glance | ||
| Rank | #19 | #20 |
| Score | 58.8 | 58.7 |
| GitHub stars | 895 | — |
| Popularity | 67.8 | 43.2 |
| Activity | 51.3 | 98.6 |
| Community | 75.5 | 57.8 |
| Research | 53.8 | 50.2 |
| Fundamentals | ||
| Description | A Virtual Knowledge Graph system that exposes relational databases as RDF knowledge graphs, translating SPARQL queries into SQL without moving data. Uses R2RML mappings and lightweight ontologies. | An RDF-based knowledge graph database with OWL 2 reasoning and property graph extensions. Includes Voicebox, an OpenAI-compatible natural language query interface via LLM integration. |
| Vendor | Ontopic | Stardog Union |
| Model | RDF | RDF |
| Kind | query-engine | database |
| Category | Established | Enterprise |
| First released | 2009 | 2011 |
| Status | active | active |
| License | Apache-2.0 | Proprietary |
| Written in | Java | Java |
| Query languages | SPARQL | SPARQL, SQL, GraphQL |
| gdotv support | no | yes |
Feature scores — not surveyed for Ontop
| Feature | Ontop | Stardog |
|---|---|---|
| Community & Business | ||
| Active development | — | 0.5 |
| Commercial support | — | ✓ |
| Live community | — | ✓ |
| Open Source | — | · |
| Pricing | — | · |
| Trendiness | — | ✓ |
| Deployment | ||
| Containerization | — | ✓ |
| Work as dedicated instance | — | ✓ |
| Work as embedded | — | · |
| Testing in-memory version | — | · |
| Platform | ||
| Operating on Linux | — | ✓ |
| Operating on Windows | — | · |
| SaaS offering | — | ✓ |
| Operations | ||
| Automatic updates | — | · |
| Client side caching | — | · |
| Data versioning support | — | · |
| Live backups | — | ✓ |
| Distribution | ||
| Cluster Re-balancing | — | · |
| Data Distribution | — | · |
| High-Availability | — | ✓ |
| Query Distribution | — | ✓ |
| Replication support | — | ✓ |
| Developer Experience | ||
| Data types defined | — | 0.5 |
| Logging/Auditing | — | ✓ |
| Object-Graph Mapper | — | · |
| Reactive programming | — | ✓ |
| Documentation up-to-date | — | ✓ |
| Binary protocol | — | · |
| CLI | — | ✓ |
| GUI | — | ✓ |
| Data Model | ||
| Multi-database | — | ✓ |
| Graph-native data | — | · |
| REST API | — | ✓ |
| Query Language | — | ✓ |
| Transactions | ||
| Granular locking | — | ✓ |
| Multiple isolation levels | — | ✓ |
| Read committed transaction | — | · |
| Transaction support | — | ✓ |
| Schema & Security | ||
| Constraints | — | ✓ |
| Schema support | — | ✓ |
| Secondary indexes | — | ✓ |
| Server side procedures | — | ✓ |
| Triggers | — | · |
| Authentication | — | ✓ |
| Authorization | — | ✓ |
| Data encryption | — | · |
Links
- Ontop · website · github · full profile
- Stardog · website · full profile