Pattern Matching¶

Pattern matching is the core of Cypher. This guide covers node and edge patterns in detail.

Node Patterns¶

// Any node
(n)

// Node with label
(p:Person)

// Node with multiple labels
(e:Person:Employee)

// Node with properties
(p:Person {name: 'Alix'})

// Anonymous node (no variable)
(:Person)

Edge Patterns¶

// Outgoing edge
(a)-[:KNOWS]->(b)

// Incoming edge
(a)<-[:KNOWS]-(b)

// Either direction
(a)-[:KNOWS]-(b)

// Any edge type
(a)-[r]->(b)

// Edge with properties
(a)-[:KNOWS {since: 2020}]->(b)

Complex Patterns¶

// Chain of relationships
MATCH (a:Person)-[:KNOWS]->(b)-[:KNOWS]->(c)
RETURN a.name, b.name, c.name

// Multiple patterns
MATCH (a:Person)-[:KNOWS]->(b), (a)-[:WORKS_AT]->(c)
RETURN a.name, b.name, c.name

// Triangle pattern
MATCH (a)-[:KNOWS]->(b)-[:KNOWS]->(c)-[:KNOWS]->(a)
RETURN a.name, b.name, c.name

Multiple Relationship Types¶

// Match any of multiple types
MATCH (a)-[:KNOWS|:WORKS_WITH]->(b)
RETURN a.name, b.name

// Match with type variable
MATCH (a)-[r:KNOWS|:WORKS_WITH]->(b)
RETURN a.name, type(r), b.name

Optional Patterns¶

// Return results even if pattern doesn't match
MATCH (p:Person)
OPTIONAL MATCH (p)-[:HAS_PET]->(pet)
RETURN p.name, pet.name

A WHERE right after an OPTIONAL MATCH decides which matches count, also when it reads a variable bound before: a row none of whose matches pass it keeps null. An OPTIONAL MATCH can also start a query (no match gives one row of nulls), and EXISTS { } and COUNT { } take OPTIONAL MATCH clauses.