Cypher is the declarative query language for Neo4j, the world's leading graph database.
The key principles and capabilities of Cypher are as follows:
Cypher matches patterns of nodes and relationship in the graph, to extract information or modify the data
Cypher has the concept of identifiers, which denote named, bound elements and parameters
Cypher can create, update, and remove nodes, relationships, labels, and properties
You can try Cypher snippets live in the Neo4j Console at console.neo4j.org or read the full Cypher documentation at docs.neo4j.org. For live graph models using Cypher, check out the graph gists at gist.neo4j.org as well.
Note
{value} denotes either literals (for ad hoc Cypher queries) or parameters, which is the best practice for applications. Neo4j properties can be strings, numbers, Booleans, or arrays. Cypher also supports maps and collections.
For your convenience, we included the online version of the Cypher refcard (http://docs.neo4j.org/refcard/2.1.1/) in unaltered form in this book. This refcard is published online under the Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license, details of which can be found at http://creativecommons.org/licenses/by-sa/3.0/.