What is it?
Neo4j is a ACID compliant, schema-less graph-based database, which stores data as nodes, relationships, and properties instead of table and documents. It’s mainly used for social networks, geospatial data, and use-cases where the how data is related is more important than the data value itself.
Modelling
Regardless of the data inputted in Neo4j, it will always follow a graph structure, which can be represented as:
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Nodes
Represent the entities of a domain (discrete objects). Labels are used to group (or classify) different nodes to the same set, and each node can contain multiple labels. A node can also contain a set of key-value properties.
CREATE (:FirstLabel:SecondLabel {first: 'My value', second: 123})-
Relationships
Describes the connection between two nodes, or the same node to itself. It’s normally the main data component of a graph-based database. This are also known as edges.
Querying
Neo4j uses Cypher as it’s query language. SQL is to relational databases as Cypher is to Neo4j and other graph-oriented databases.