The document discusses the author's experience with NoSQL databases from a Java developer perspective. Prototypes were created using Voldemort, CouchDB, and Neo4J. Implementing connectors for new databases required creating new Java classes, mappings, and DDL for each. CouchDB provides a simpler approach with three document types, a schemaless structure, elastic extensibility, and direct mapping between Java beans and JSON without an ORM or need for deep ORM knowledge.

1. NoSQL from Java
developer PoV
@_dagi from @gooddata
Tuesday 25 January 2011

2. NoSQL Experiences
• Few prototypes on top of NoSQL
databases
• Voldemort
• CouchDB
• Neo4J
Tuesday 25 January 2011

3. Tables/Entities
Integration
1 1
0...* 0...*
Connector
Connector Log
Connector
Connector
Connector
Tuesday 25 January 2011

4. Implementation details
• Java classes
• ORM mapping (Hibernate)
• DDL schema
Tuesday 25 January 2011

5. What’s wrong
• Every new connector
• new Java class
• new mapping
• DDL
• 3rd party libraries
• ~ 5-10
• ORM/Hibernate/Transactions deep
knowledge
Tuesday 25 January 2011

6. What’s wrong
• Every new connector ed
• new Java class ica
t
• new mappingp l e
m p l
• DDLco im !
3rdo s se s
• o r ca
party libraries
T ~ 5-10fo e
•
u s
• ORM/Hibernate/Transactions deep
knowledge
Tuesday 25 January 2011

7. Make things as simple
as possible, but not
simpler.
Tuesday 25 January 2011

8. CouchDB
• 3 document types
• Integration, Log, Connector
• Schemaless (No DDL)
• Elastic extensibility
• Java bean <=>JSON mapping
• HTTP client
Tuesday 25 January 2011

9. ORM/RDBMS vs NoSQL
ORM/RDBMS NoSQL
Java model classes Java model classes
JPA mapping JSON mapping
DDL
Hibernate + 3rd libs
ORM deep knowledge Semantic of HTTP methods
SQL/OQL Map/Reduce
Tuesday 25 January 2011