A graph model is a data model which is basically a network-like structure. A graph model stores the data in the form of Vertices (Nodes) which are interconnected with the help of Arcs (Edges). The original artifacts of this graph model are the edge and vertex.

Vertex – Vertex is an entity which can be connected with other Vertices and it has the following properties:
  • It is a unique identifier
  • It has a set of incoming Edges
  • It has a set of outgoing Edges
Edge – Edge is an entity that connects the two Vertices, and it has the following properties:
  • It is a unique identifier
  • It links to an incoming Vertex (also known as head)
  • It relates to an outgoing Vertex (also known as tail)
  • It is a label that defines the type of connection/relationship between head and tail vertex.

Point to be noted: Go through this Q&A very thoroughly as this is one of the essential CouchDB interview questions.

BY Best Interview Question ON 10 Apr 2019