Queries

1. Display database schema
   1. Basically displaying all types of nodes and relationships between each type of node
   2. CALL db.schema.visualization();
2. Data import
   1. See the stackoverflow sample dataset for JSON import from url
   2. Data Import - Developer Guides (neo4j.com)

Basic Queries

Find labels and their frequencies

Label is basically node name/type.

MATCH (n)
RETURN labels(n) as label, count(*) as freq
ORDER BY freq DESC;

Find all relationship types and their frequencies

MATCH ()-[r]->()
RETURN type(r) as type, count(*) as freq
ORDER BY freq DESC;

()-[r]->() is used to express relationship. The middle term is relationship. Left and right of the relationship are both nodes. (A)-[reads]->(B) means A reads B. The relation is the same as the direction of the arrow.

Sorting by Attribute Count

What are the most popular tags?

MATCH (q:Question)-[:TAGGED]->(t:Tag)
RETURN t.name, count(q) AS questions
ORDER BY questions DESC
LIMIT 5;

Find all question tags, and count question for each tag.

Path Finding

Find all shortest paths between 2 users with whatever relationships in between.

MATCH path = allShortestPaths(
(u1:User {display_name:"alexanoid"})-[*]-(u2:User {display_name:"InverseFalcon"}))
RETURN path LIMIT 1;

Reference

• Cypher Cheat Sheet - Neo4j Documentation Cheat Sheet