This is a talk about how we can use NoSQL to drive better design. Lucas gave variations of that talk at RubyConf India and Abril Pro Ruby Brazil.

1. Escaping the
Tower of Babel
Domain Driven Design & NoSQL

2. class SpaceShuttle
end
!
class Astronaut
end
vI

3. Domain Driven Design
• Find an ubiquitous language
• The language is based on the domain
• Every person involved understands the
language
Eric Evans

4. Iterative Development
Close relationship
between
devs & domain experts
Domain Driven Design

5. Hi.
I’m Lucas.

6. I work for
ArangoDB GmbH

7. We build
ArangoDB

8. ArangoDB
is an Open Source
NoSQL Database

9. But what is NoSQL?

10. SQL
NoSQL

11. SQL
Not only SQL

12. What is NoSQL?
What is SQL?
What is a relational
algebra?
What is a relation?
Not SQL
A relational algebra
An algebra on relations

13. {(Alice, 1983-07-1, 1)
(Bob, 2014-03-19, 2)}

14. name birthday city
Alice 1983-07-1 1
Bob 2014-03-19 2

15. Disconnect
I
v
Ownership
name: alice…
type: spaceshuttle

16. Entity Value Object Service
Identified by ID Value What it does
State Mutable Immutable Stateless

17. + Factories
+ Repositories
+ Aggregates

18. DENORMALIZATION

19. Lift the
restriction
• Tuples with arbitrary attributes
• Tuples containing other Tuples

20. Space Shuttle
Parts

21. Space Shuttle
Parts
Document
Store

22. Itype:
spaceshuttle
vname:
alice
astronaut: 1
spaceshuttle: 3

23. JOINS

24. Alice Ownership SpaceShuttle

25. Alice Ownership SpaceShuttle
Graph
Database

26. Alice Ownership
SpaceShuttle
Parts

27. Alice Ownership
SpaceShuttle
Parts
I’m a
document!

28. Alice Ownership
SpaceShuttle
Parts
Me too!

29. Alice Ownership
SpaceShuttle
Parts

30. Alice Ownership
SpaceShuttle
Parts
Multi Model
Database

31. Disconnect
I
v
Ownership
name: alice…
type: spaceshuttle

32. Itype:
spaceshuttle
vname:
alice
Ownership
since:
2003

33. Explain graphs.
Learn about the domain.
Find the common language.
Build one model for everyone involved.
Evolve the model alongside the implementation
moonglum
moonbeamlabs
arangodb.org