Key operative words in Cypher

Like every database query language, there are a few operative words that have an important meaning in the composition of every query. It's useful for you to know these since you will be using them to compose your specific queries on your specific datasets.

Keyword	Function	Example
MATCH	This describes a pattern that the database should match. This is probably the most important piece of the query as it is a structural component that always starts your queries.	MATCH (me:Person)-[:KNOWS]->(friend)
WHERE	This filters results that are found in the match for specific criteria.	WHERE me.name = "My Name" AND me.age > 18
RETURN	This returns results. You can either return paths, nodes, relationships, or their properties—or an aggregate of the mentioned parameters. This is another structural component, as all read queries and most write queries will return some data.	RETURN me.name, collect(friend), count(*) as friends
WITH	This passes results from one query part to the next. Much like RETURN, but instead of including data in the result set, it will be passed to the following part of the query. It transforms and aggregates results and also separates READ and UPDATE statements.
ORDER BY SKIP LIMIT:	This sorts and paginates the results.	ORDER BY friends DESC SKIP 10 LIMIT 10
CREATE	This creates nodes and relationships with their properties.	CREATE (p:Person), (p)-[:KNOWS {since: 2010}]-> (me:Person {name:"My Name"})
CREATE UNIQUE	This fixes graph structures by only creating structures if they do not yet exist.
MERGE	This matches or creates semantics by using indexes and locks. You can specify different operations in case of a MATCH (part of the pattern already existed) or on CREATE (pattern did not exist yet).	MERGE (me:Person {name:"My Name"}) ON MATCH me SET me.accessed = timestamp() ON CREATE me SET me.age = 42
SET, REMOVE	This updates properties and labels on nodes and/or relationships.	SET me.age = 42SET me:Employee REMOVE me.first_name REMOVE me:Contractor
DELETE	It deletes nodes and relationships.	MATCH (me) OPTIONAL MATCH (me)-[r]-() DELETE me, r

With these simple keywords, you should be able to start forming your first Cypher queries. After all, it's a bit like ASCII art, a structure similar to the one shown in the following diagram:

This is very easily described in Cypher as:

(a:Person {name:"Rik")–[:OWNS]–>(b:Device {brand:"LIFX"})

All we need to do to make this a proper Cypher statement is to wrap it in MATCH and RETURN statements:

Match
(a:Person {name:"Rik")–[r:OWNS]–>(b:Device {brand:"LIFX"})
return a,r,b;

This is just a simple example of how you would start using Cypher. More complex examples can of course be found elsewhere in this book. You can also find the complete Cypher Ref Card (online version at http://docs.neo4j.org/refcard/2.1/) included in the final pages of this book.