social-movie-db.adoc

Movie Database

Our example graph consists of movies with title and year and actors with a name. Actors have ACTS_IN relationships to movies, which represents the role they played. This relationship also has a role attribute.

We’ll go with three movies and three actors:

CREATE (matrix1:Movie {title : 'The Matrix', year : '1999-03-31'})
CREATE (matrix2:Movie {title : 'The Matrix Reloaded', year : '2003-05-07'})
CREATE (matrix3:Movie {title : 'The Matrix Revolutions', year : '2003-10-27'})
CREATE (keanu:Actor {name:'Keanu Reeves'})
CREATE (laurence:Actor {name:'Laurence Fishburne'})
CREATE (carrieanne:Actor {name:'Carrie-Anne Moss'})
CREATE (keanu)-[:ACTS_IN {role : 'Neo'}]->(matrix1)
CREATE (keanu)-[:ACTS_IN {role : 'Neo'}]->(matrix2)
CREATE (keanu)-[:ACTS_IN {role : 'Neo'}]->(matrix3)
CREATE (laurence)-[:ACTS_IN {role : 'Morpheus'}]->(matrix1)
CREATE (laurence)-[:ACTS_IN {role : 'Morpheus'}]->(matrix2)
CREATE (laurence)-[:ACTS_IN {role : 'Morpheus'}]->(matrix3)
CREATE (carrieanne)-[:ACTS_IN {role : 'Trinity'}]->(matrix1)
CREATE (carrieanne)-[:ACTS_IN {role : 'Trinity'}]->(matrix2)
CREATE (carrieanne)-[:ACTS_IN {role : 'Trinity'}]->(matrix3)

This gives us the following graph to play with:

Let’s check how many nodes we have now:

START n=node(*)
RETURN "Hello Graph with " + count(*) + " Nodes!" AS welcome;

Return a single node, by name:

MATCH (movie:Movie)
WHERE movie.title = 'The Matrix'
RETURN movie;

Return the title and date of the matrix node:

MATCH (movie:Movie)
WHERE movie.title = 'The Matrix'
RETURN movie.title, movie.year;

Which results in:

Show all actors:

MATCH (actor:Actor)
RETURN actor;

Return just the name, and order them by name:

MATCH (actor:Actor)
RETURN actor.name
ORDER BY actor.name;

Count the actors:

MATCH (actor:Actor)
RETURN count(*);

Get only the actors whose names end with ``s'':

MATCH (actor:Actor)
WHERE actor.name =~ ".*s$"
RETURN actor.name;

Here’s some exploratory queries for unknown datasets. Don’t do this on live production databases!

Count nodes:

START n=node(*)
RETURN count(*);

Count relationship types:

START n=node(*)
MATCH (n)-[r]->()
RETURN type(r), count(*);

List all nodes and their relationships:

START n=node(*)
MATCH (n)-[r]->(m)
RETURN n AS from, r AS `->`, m AS to;