Database_Graph

Graph Database

• Represents data using graphs
• Consist of Vertices and Edges

Graph Database Models

• Property Graph model
  • Vertex:
    • ID
    • Properties (key-value pairs)
    • Outgoing edges
    • Incoming edges
  • Edge:
    • ID
    • Properties (key-value pairs)
    • Label (Relationship)
    • Head Vertex
    • Tail Vertex
  • Used by: Neo4j, Titan, InfiniGraph, JanusGraph
• Triple Store model
  • (Subject, predicate, Object)
    • Object can be primitive
      • Example: (Lucy, age, 33)
    • Object can be Vertex
      • Example: (Lucy, marriedTo, Alain)
  • Used by: Datomic, AllegroGraph

Query Languages

• Datalog
  • oldest
  • used in Datomic DB
• Cypher
  • used in Neo4j DB
• SPARQL
  • SPARQL Protocol And RDF Query Language
  • Query Language for triple stores using RDF model
  • Inspired by Cypher
• Gremlin
  • used in JanusGraph

Apache TinkerPop

• Graph computing framework for OLTP and OLAP graph systems
• The query language is Gremlin
• https://tinkerpop.apache.org/providers.html
• Implementations
  • JanusGraph
  • Neo4j
  • Azure CosmosDB for Gremlin
  • Amazon Neptune