NEO4J ESSENTIALS

Tuna VARGI

DOWNLOAD NEO4J

http://neo4j.com/download/

Why graphs?

What is graph ?

USE CASES

SOCIAL NETWORK

NETWORK ANALYSIS

ROUTE FINDING

RECOMMENDATIONS

SECURITY ANALYSIS

ETC

WHAT IS GRAPH ?

BLOCKS

• Nodes
• Relationships
• Properties
• Labels

RELATIONAL DB

GRAPH DB

CYPHER

a pattern-matching query language for graphs 

DECLARATIVE

PATTERN MATCHING

EXPRESSIVE

CLAUSES

GENERAL CLAUSES

• RETURN
• ORDER BY
• LIMIT

READING CLAUSES

• MATCH
• OPTIONAL MATCH
• WHERE
• WITH
• AGGREGATION

WRITE CLAUSES

• CREATE
• MERGE
• SET
• DELETE
• REMOVE

QUERY STRUCTURE

MOVIES

PERSON

RELATIONSHIPS

• ACTED_IN
• DIRECTED
• FOLLOWS
• PRODUCED
• REVIEWED
• WROTE

QUERY EXAMPLES

MATCH (m:Movie) 
WHERE m.released=1992
RETURN m

MATCH (m:Movie), (p: Person)
MATCH path=(m)<-[:ACTED_IN]-(p)
WHERE m.released=1992
return path

MATCH (m:Movie), (p: Person {name: "Tom Hanks"})
MATCH (p)-[:DIRECTED]->(m)
return m

MATCH (m:Movie)<-[:ACTED_IN]-(a:Person)

 RETURN m.title as movie, collect(a.name) as cast

 LIMIT 20

MATCH (p: Person {name: "Tom Hanks"})
MATCH (p)-[:DIRECTED]->(m:Movie)

WITH distinct m
return count(m)

CHROMA

WHAT WAS OUR PROBLEM ?

INFINITE CATEGORY TREE

PHOTOS ATTACHED TO CATEGORIES

GIVE ME THE LATEST PHOTO IN A CATEGORY TREE

MATCH (category:Category{id:'5294ecd1389a5e44303bd774'})
MATCH (category)-[:CHILD_OF*0..50]->(subcats: Category)<-[:PHOTO_OF]-(photo: Photo)
with photo
order by photo.created_at
return last(collect(photo.id)) as last_photo_id

WE NEED THE LATEST PHOTO IN A CATEGORY TREE BELONG TO PROVIDED USER

COMPLEX AGGREGATION

MATCH (cat_user:User {id:"51e52cfc389a5e35fa403436"}),
      (category:Category)
WHERE category.parent_id='0'
MATCH (category)-[:CHILD_OF*0..50]->(subcats)
WITH distinct subcats as dsubcats, category, cat_user
MATCH (dsubcats)<-[:PHOTO_OF]-(photo:Photo)-[:OWNER]->(cat_user)
with photo, category, cat_user
order by photo.created_at
return distinct category.id, last(collect(photo.id)) as last_photo_id, count(distinct photo) as photo_count, category.name

GIVE ME THE PHOTOS CONNECTED TO PLACES NEAR LAT 22.7 LON 79.10

START place=node:geom('withinDistance:[22.7, 79.10, 100.0]')
        where place.type='Place'
        MATCH (place)-[:CHILD_OF*0..50]->(subplaces:Place)
        with distinct subplaces, place
        MATCH (subplaces)<-[:TAKEN_AT]-(photo:Photo)
        return place.name, photo

GIVE ME THE COUNT OF PHOTOS IN NORTH AMERICA FOR WILD ANIMALS

MATCH (place: Place{id: '5571b6a691201b05075468f8'})
MATCH (category: Category{id: '529500b0389a5e442fd8fcad'})
MATCH (place)-[:CHILD_OF*0..10]->(subplaces)<-[:TAKEN_AT]-(photo:Photo)
MATCH (category)-[:CHILD_OF*0..10]->(subcategories: Category)<-[:PHOTO_OF]-(photo: Photo)
return count(distinct photo)

THANKS