1. An introduction to MongoDB
Russell Smith

2. /usr/bin/whoami
• Russell Smith
• Consultant for UKD1 Limited,
• External consultant for 10gen
• Help with code, architecture, infrastructure, devops, sysops, capacity
planning, etc
• <3 MongoDB, MySQL, Redis, Gearman, Neo4j, Kohana, Riak, PHP,
Debian, AWS, etc

3. What is MongoDB
• A scalable, high-performance, open source, document-oriented
database.
• Stores JSON like documents
• Commercially backed by 10gen

4. Why choose it?
• Schema-less
• Simple
• Reliable
• Scalable
• Drivers

5. Who uses it?
• Foursquare
• Disney
• Craigslist
• MTV Networks
• O2
• Telefonica

6. Basics
• insert
• find
• update
• remove
• ensureIndex

7. Insert
• db.test.insert({hello: ‘world’});

8. Find
• db.test.find()
• Equivalent of SELECT * FROM test;
> db.test.insert({hello: ‘world’});
> db.test.find();
{ "_id" : ObjectId("4e7c9f464bdd7534bc498ff7"), "hello" : "world" }

9. Updating
• db.test.update(<condition>, <operation>)
> db.test.find();
{ "_id" : ObjectId("4e7c9f464bdd7534bc498ff7"), "hello" : "world" }
> db.test.update({hello:‘world’}, {hello: ‘seedhack’});
> db.test.find();
{ "_id" : ObjectId("4e7c9f464bdd7534bc498ff7"), "hello" : "seedhack" }

10. Removing
• db.test.remove(<condition>)
> db.test.find();
{ "_id" : ObjectId("4e7c9f464bdd7534bc498ff7"), "hello" : "seedhack" }
> db.test.remove({hello: ‘seedhack’});
> db.test.count()
0
>

11. Indexes
• It’s usually a good idea to index your collections
• How and which columns depends on what you are doing
• explain
> db.test.ensureIndex({hello:1})

12. More advanced
• sort, count, limit, special operators
• Capped collections
• Geospatial indexing
• MapReduce
• Replica sets
• Sharding

13. Getting started...
• Download & install - http://www.mongodb.org/downloads
• Online shell - http://www.mongodb.org/

14. Questions / Further
• Come and ask me questions
• Updates can also push, set, increment, decrement, etc
http://bit.ly/gEfKOr
• Indexes can be across multiple keys, 2D (geo) and ASC / DESC
http://bit.ly/hpK68Q
• SQL -> Mongo chart
http://bit.ly/ig1Yfj