Creating and Modifying Data

Now that you can read data with MATCH and WHERE, it is time to learn how to create, update, and delete data in Neo4j using Cypher.

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CREATE — Adding New Data

The CREATE clause adds new nodes and relationships to the graph:

Create a node

CREATE (p:Person {name: "Alice", age: 30})
RETURN p

Create multiple nodes

CREATE (a:Person {name: "Alice", age: 30})
CREATE (b:Person {name: "Bob", age: 25})
RETURN a, b

Create a relationship

MATCH (a:Person {name: "Alice"})
MATCH (b:Person {name: "Bob"})
CREATE (a)-[:FRIENDS_WITH {since: 2022}]->(b)

Create nodes and relationships together

CREATE (a:Person {name: "Alice"})-[:WORKS_AT {role: "Engineer"}]->(c:Company {name: "Acme"})
RETURN a, c

Important: CREATE always creates new data. If a node with the same properties already exists, it will create a duplicate.

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MERGE — Create If Not Exists

MERGE is the idempotent alternative to CREATE — it only creates data if it does not already exist:

Merge a node

MERGE (p:Person {name: "Alice"})
RETURN p

If a :Person node with name: "Alice" exists, it is returned. If not, it is created.