A lightening talk introducing MongoDB

1. A short introduction to MongoDB
Russell Smith

2. /usr/bin/whoami
• Russell Smith
• Consultant for UKD1 Limited
• Specialising in helping companies going through rapid growth
• Help with code, architecture, infrastructure, devops, sysops, capacity
planning, etc
• <3 gearman, mongodb, neo4j, mysql, kohana, riaksearch, php, debian

3. What is MongoDB
• A scalable, high-performance, open source, document-oriented
database.
• Stores JSON like documents
• Indexible on any attributes (like MySQL)

4. Getting started...
• Try out the interactive shell at www.mongodb.org (then click try!)
• Download and install - http://www.mongodb.org/downloads

5. Basics
• Common things you do in MySQL or another RDBMS;
• Insert
• Select (aka find)
• Update
• Delete (aka remove)
• Index

6. Create
• Creating ‘tables’, or in MongoDB terms collections, is not usually
necessary
• Ditto for databases

7. Insert
• db.test.insert({hello: ‘world’});
• This insert the document {hello: ‘world’} into the test collection

8. Let’s check it
• In MongoDB we find documents rather than SELECTing them...
• db.test.find()
• this is the equivalent of SELECT * FROM test;
• it will return the document we previously inserted

9. Updates
• Let’s update the document to say from Russell
• db.test.update(<documents which match>, <set to x>)
• db.test.update({hello: ‘world’}, {hello: ‘from Russell’})

10. Delete?
• db.test.remove(<where documents match>)
• Lets remove the last document
• db.test.remove({hello: ‘from Russell’})

11. Drop
• If you no longer want an entire collection, you can drop it which
removes all the data and indexes;
• db.test.drop()

12. Indexes
• For performance it’s usually a good idea to index your collections.
• How and which columns depends on what queries you are doing - you
can get help with this by using ‘explain’ much like in MySQL.
• db.test.ensureIndex({hello:1})

13. Further reading
• I’ve only brushed on the details, but this should be enough to get you
interested / started with MongoDB. Some of the missing stuff;
• 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