This document discusses using MongoDB as an agile NoSQL database for big data applications. It describes MongoDB's schema-less design, horizontal scaling, and replication capabilities which make it a good fit for frequently changing agile projects. The document includes examples of using MongoDB for an e-commerce catalog with dynamic product data and reviews from multiple sources.

1. An Agile NoSQL Database
Gaurav Awasthi
Technology Evangelist
gawasthi@equalexperts.com

2. Big Data - The New World Order
• A massive volume of both structured and unstructured data that it's
difficult to process using traditional database and software techniques
• As of 2012, every day 2.5 quintillion bytes of data were created
• Data Source:
– Climate sensors
– Social media
– Digital pictures and videos
– Purchase transaction records
– Cell phone GPS signals
• Characteristics : Volume, Velocity and Variety
• Key Usage: leverage data-driven strategies to innovate, compete, and
capture value from deep and up-to-real-time information

3. NoSQL
Defining Characteristics
– Scaling out on commodity hardware
– Aggregate structure
– Schema-less attitude
– Impedance Mismatch : Relational model in-memory data structures
– Big Data : Massive data being stored and transacted
– Reduced Data Management and Tuning Requirements
– Eventually consistent / BASE (not ACID)

4. Mongo DB
• Open-source, Document-oriented, popular for its agile and scalable
approach
• Notable Features :
– JSON/BSON data model with dynamic schema
– Auto-sharding for horizontal scalability
– Built-in replication with automated fail-overs
– Full, flexible index support including secondary indexes
– Rich document-based queries
– Aggregation framework and Map / Reduce
– GridFS for large file storage

5. Agile & MongoDB
Characteristics supporting Agility
– Allows dynamic schema (schemaless)
– JSON format, which maps well to object-style data.
– Simplified db tuning
– Cost Effective and Simple replica sets
– Easy scale out due to simplified sharding mechanism
– Rich content using GridFS

6. A Demo for Schema-less way

7. A Demo Query Plan and DB
Tuning

8. Replication
• Replica set – a mongod cluster
• Ensures High Availability, Redundancy, Automated Fail-
over
• Writes to the Primary, Reads from all
• Asynchronous replication
• In conventional terms, more like Master/Slave replication
• Members can be configured to be: Secondary only /
Non- Voting / Hidden / Arbiters / Delayed

9. Elastic Architecture

10. A Demo for Replica Set
• Run the 3 mongod processes
• Demo that they are running on different ports using ps –ef
• Initiate the repl set and add members
• Demo which ones are primary and secondary using rs.status()
• Now insert docs into a collection in primary
• Demo that its replicated to secondary
• Thereby proving how straight fwd is replication
• Briefly touch upon the steps for sharding too

11. Case Study – E-Commerce Shop
Architecture Diagram
Product supplier
catalog App External Feeds
(container) Mongo
Payment Gateway

12. Domain model

13. JSON structure
{"_id" : "compatibleHandsets" : [{
ObjectId("5082626144ae3a6879 "manufacturer" : {
19c094"), "name" : "Apple",
"name" : "iPhone 5 Pop Blue Case", "canonicalName" : "apple"
},
"canonicalName" : "iphone-5-pop-
blue-case", "model" : "iPhone 5 16GB",
"name" :
"retailPrice" : 19.99, "Apple_iPhone_5_16GB",
"productCode" : "G4IC542G", "canonicalName" :
"category" : { "apple_iphone_5_16gb"
}],
"categoryCode" : "CAS",
"name" : "Cases",
review_ids : ["review_id1",
"canonicalName" : "cases" "review_id2"]
}, }

14. Design decisions with Mongo
• Agile incremental releases
• Unstructured data from multiple suppliers
• GridFS : Stores large binary objects
• Spring Data Services
• Embedding and linking documents
• Easy replication set up for AWS

15. Conclusion and Thanks
MongoDB: the right persistence tool for Agile Development for multitude of
business problems in the new world order
References:
•
Mongodb.org