Property graph

A property graph, labeled property graph, or attributed graph is a data model of various graph-oriented databases,^[1] where pairs of entities are associated by directed relationships, and entities and relationships can have properties.

In graph theory terms, a property graph is a directed multigraph, whose vertices represent entities and arcs represent relationships. Each arc has an identifier, a source node and a target node, and may have properties.

Properties are key-value pairs where keys are character strings and values are numbers or character strings. They are analogous to attributes in entity-attribute-value and object-oriented modeling. By contrast, in RDF graphs, "properties" is the term for the arcs. This is why a clearer name is attributed graphs, or graphs with properties.

This data model emerged in the early 2000s.