Popular Graph Databases

51 from taxonomy, but highlights:

• Neo4j: Native LPG, Cypher, enterprise-ready.
• OrientDB: Multi-model (graph + document).
• Virtuoso: RDF focus.
• JanusGraph: Distributed, on Cassandra.

Explaining Neo4j in Depth

Leading native LPG with Cypher, ACID, clustering for scale.

Why top: Mature ecosystem, high perf.

Code Sample:

MATCH (n) RETURN n

Explaining OrientDB in Depth

Combines graph, document, key-value.

Why versatile: Multi-paradigm apps.

Code Sample (Orient SQL):

SELECT FROM V

Explaining Virtuoso in Depth

RDF/triple store with SPARQL.

Why semantic: Linked data.

Code Sample (SPARQL):

SELECT * WHERE { ?s ?p ?o }

Explaining JanusGraph in Depth

Scalable on backends like Cassandra.

Why big data: Distributed processing.

Code Sample (Gremlin):

g.V()

flowchart LR
    Neo4j["Neo4j"] --> Neo4jCypher["Cypher"]
    Neo4j --> Neo4jCluster["Clustering"]
    OrientDB["OrientDB"] --> OrientGraph["Graph"]
    OrientDB --> OrientDocument["Document"]
    Virtuoso["Virtuoso"] --> VirtuosoModel["RDF"]
    Virtuoso --> VirtuosoQuery["SPARQL"]
    JanusGraph["JanusGraph"] --> JanusStorage["Cassandra"]
    JanusGraph --> JanusQuery["Gremlin"]

Compare:

DB	Model	Native?	Query Lang	Strengths
Neo4j	LPG	Yes	Cypher	Speed, flexibility
OrientDB	Multi	Yes	SQL-like	Versatile
Virtuoso	RDF	No	SPARQL	Semantic web
JanusGraph	LPG	Yes	Gremlin	Distributed