This document summarizes the key new features in Neo4j 2.0, including labels, schema indexing, the MERGE operation, and transactional Cypher. Labels allow nodes to be identified and queried by type. Schema indexing improves performance. MERGE combines matching and creating behavior. Transactions make Cypher requests more robust. The focus is on further developing Cypher as a graph query language.

1. Innovate. Share. Connect.
Boston June 10-11
What's new in Neo4j 2.0What's new in Neo4j 2.0
Andreas Kollegger, Neo TechnologyAndreas Kollegger, Neo Technology
@akollegger@akollegger

2. Neo4j 2.0
★ 3 questions: Why? What?
How?
★ with just One answer

3. Why 2.0?

4. Why 2.0?
• Neo4j 1.10 could be an AM radio station
• Wanted to seem web-savvy before it goes to 3.0
• We were in the mood to break some things
• Really, it's because of a shift in focus

5. (0.x) --> (1.x) --> (2.x)
• 0.x was about embedded java
• 1.x introduced the server and REST
• 2.x ease of use, big data, cloud
which means a focus on...

6. This guy

7. Focus on Cypher
• Cypher, a carefully crafted language for working with
graphs
• Declarative, friendly, easy to read and write
• One language, used everywhere
• REST for management, Java for plugins,

8. What is new in 2.0?

9. There will be
some sad Danes
some sad Danes
"Once you label me,
you negate me.”
- Søren Kierkegaard

10. • Simply: a label identifies a set of nodes
• Nodes can have multiple labels
• Find nodes by label
• Constrain properties and values
• (lightweight schema)
• A simple idea, with powerful applications
Introducing Node Labels

11. Find friends who like cheese
MATCH (max:People)-[:FRIENDS]->(cheesy: People),
(cheesy)-[:LIKE]->(cheese:Things)
WHERE max.name = "Max De Marzi"
AND cheese.name = "Cheese"
RETURN cheesy;

12. Schema Indexing
• Indexes for labels, based on a property
• Simple lookups for now
• Unique indexing coming soon
• Full-text, other special indexes in planning
CREATE INDEX ON :People(name)

13. MERGE operation
• a combination of MATCH + CREATE
• replaces CREATE UNIQUE
• attempts to MATCH, with specified properties and labels
• if match fails, new graph data is created
• optional sub-clauses for handling ON CREATE, and ON
MATCH
MERGE (charlie { name:'Charlie Sheen', age:10 })
RETURN charlie

14. • begin, commit, or rollback a transaction
• transaction as RESTful resource
• issue multiple statements per request
• multiple requests per transaction
• compact response format
Transactional Cypher

15. Anything else?
• Performance improvements
• Breaking changes to some APIs (read CHANGES.txt)
• Migration of "legacy" indexes (stop STARTing)
• Mandatory transactions for all DB interactions
• Improving installers (in progress)
• Changing everything to be "all Cypher, all the time"

16. How to use labels?

17. Label - to identify
name: Ford Prefect
NINO: 122-762-9255
HIKE: 415-484-6364
UKUK
H2G2H2G2

18. Label - to identify
UKUK
H2G2H2G2
MATCH (ford:H2G2) WHERE ford.HIKE = '415-484-6364' RETURN ford

19. Label - to avoid confusion
name: Ford Prefect name: Ford Prefect
AlienAlien CarCar
MATCH (ford:Alien) WHERE ford.name = 'Ford Prefect' RETURN ford

20. Label - special nodes
• replace built-in reference node,
with domain specific reference nodes
4242
AnswerAnswer

21. Labels - rules of thumb
• Use a label to make queries easier to read & write
• And to improve performance through indexing
• Start with anything you might've put in a legacy index
• Use lightly, as few labels as needed

22. Is that it for 2.0?

23. Well, there is this...

27. What is new in 2.0?
• It's all about Cypher, starting with
• Labels, the first significant change in over 12 years
• Mix in schema indexing
• Then transactional REST, new clauses, functions
• A fresh Web UI that is Cypher-focused

28. Thanks :)
Any questions?
Any questions?
Any questions?
@akollegger to keep in touch