Graph Databases

Graph Databases are a type of database that emphasizes the relationships between data. It holds data in a flexible, graph format.

Graphs are characterized by nodes - the data - and edges - the relationships between the data. In a Graph Database the nodes are the records being stored, and the edges are a conceptual link between two nodes.

For instance if you're storing social network information, the nodes could be people and the edges could be the nature of their connection (PARENT_TO, FRIEND_OF, etc.). The edges are semantic in that they contain meaning about the connected records.

Graph databases are good at exploring data that has complex connections; because the data is stored as a graph, traversing the connections is often a constant time operation, much faster than the comparable operation would take in a traditional relational database.

Because of this, graph databases are particularly well suited to knowledge graphs and schema mapped data.