Cypher.md

Cypher Queries

Create Users:

WITH ["Jennifer","Michelle","Tanya","Julie","Christie","Sophie","Amanda","Khloe","Sarah","Kaylee"] AS names 
FOREACH (r IN range(0,100000) | CREATE (:User {username:names[r % size(names)]+r}));

Create Relationships:

MATCH (u1:User),(u2:User)
WITH u1,u2
LIMIT 5000000
WHERE rand() < 0.1
CREATE (u1)-[:FRIENDS {weight: rand()}]->(u2);

Create Index:

CREATE INDEX ON :User(username);

Get the network side for Khloe17 4 hops out:

MATCH (u:User{username:'Khloe17'})-[*1..4]->(c) 
RETURN count(DISTINCT c)

Takes about a second. Now take the arrow sign off:

MATCH (u:User{username:'Khloe17'})-[*1..4]-(c) 
RETURN count(DISTINCT c)

OMG, so long...

Get 10k usernames:

MATCH (n:User) 
RETURN n.username 
LIMIT 10000    

Reach Query:

MATCH p=(u:User)-[*1..2]-(u2:User) 
WHERE u.username = 'Khloe17' AND
      u2.username = 'Michelle21'      
RETURN p, REDUCE(weight = 0.0, r in relationships(p) | weight + r.weight) / length(p) AS weight
ORDER BY weight DESC
LIMIT 100

Good Friends Query:

MATCH p=(u:User)-[*1..4]-(u2:User) 
WHERE u.username = 'Khloe17' AND u2.username = 'Michelle21' AND
      ALL (r IN relationships(p) WHERE r.weight >= 0.80)
RETURN p, REDUCE(weight = 0.0, r in relationships(p) | weight + r.weight) / length(p) AS weight
ORDER BY length(p), weight DESC
LIMIT 100

Report Queries:

MATCH (u:User)-[:FRIENDS]-(u2:User)-[:FRIENDS]-(u3:User)
RETURN u.username, u2.username, u3.username
LIMIT 100

EXPLAIN MATCH (u:User)-[:FRIENDS]-(u2:User)-[:FRIENDS]-(u3:User)
RETURN u.username, u2.username, u3.username
ORDER BY u.username, u2.username, u3.username
LIMIT 100

EXPLAIN MATCH (u:User)-[:FRIENDS]-(u2:User)-[:FRIENDS]-(u3:User)
RETURN u.username, u3.username, COUNT(u2)
LIMIT 100

Analytic Query:

EXPLAIN MATCH (u:User)-[:FRIENDS]-(u2:User)-[:FRIENDS]-(u3:User)
WITH u, u3, COUNT(u2) AS counts
RETURN counts, COUNT(*)
ORDER BY counts