NoSql Tutorial 7 : Graph Stores

These are used to store information about networks, such as social connections. Graph stores include Neo4J and HyperGraphDB.
·         A graph database stores data in a graph.
·         It is capable of elegantly representing any kind of data in a highly accessible way.
·         A graph database is a collection of nodes and edges
·         Each node represents an entity (such as a student or business) and each edge represents a connection or relationship between two nodes.
·         Every node and edge is defined by a unique identifier.
·         Each node knows its adjacent nodes.
·         As the number of nodes increases, the cost of a local step (or hop) remains the same.
·         Index for lookups.
Here is a comparison between the classic relational model and the graph model :

Relational model
Graph model
Tables
Vertices and Edges set
Rows
Vertices
Columns
Key/value pairs
Joins
Edges

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