Neo4j is a high-performance, NOSQL graph database that stores structured data over the network rather than in tables. Neo4j can also be seen as a high-performance graph engine with all the features of a full-fledged database. Programmers work in an object-oriented, flexible network structure rather than rigid, static tables -- but they can enjoy all the benefits of a fully transactional, enterprise-class database.
Neo4j has attracted more and more attention due to its embedded, high-performance, lightweight and other advantages.
Neo4j is the world’s leading Graph Database. It is a high performance graph store with all the features expected of a mature and robust database, like a friendly query language and ACID transactions. The programmer works with a flexible network structure of nodes and relationships rather than static tables—yet enjoys all the benefits of enterprise-quality database. For many applications, Neo4j offers orders of magnitude performance benefits compared to relational DBs.
There are two basic data types in a graph: Nodes and Relationships. Nodes and Relationships contain key/value attributes. Nodes are connected by the relationships defined by Relationships to form a relational network structure.
Neo4j Features
1. The mismatch of object relations makes it so difficult and laborious to squeeze the object-oriented "round objects" into the relation-oriented "square tables", and all this can be avoided.
2. The static, rigid, and inflexible nature of the relational model makes it very difficult to change schemas to meet changing business needs. For the same reason, databases often hold back when development teams want to apply agile software development.
3. Relational models are poorly suited to expressing semi-structured data – and industry analysts and researchers agree that semi-structured data is the next big thing in information management.
4. The network is a very efficient data storage structure. It is no coincidence that the human brain is a huge network, and the World Wide Web is likewise structured as a mesh. The relational model can express network-oriented data, but the relational model is very weak in the ability to traverse the network and extract information.