These are some of my notes of my beginning, while learning Redis and Mongodb for a pet project. I made them for a tech talk at Maresme Developers Meetup #maresmedev. Please email email me for notifying mistakes or suggestions.

1. NOSQL
agile data storage

2. SQL: THE BEGINNING
• Data structured on tables
using columns
• Data on one column is the
key for making relationships
with other tables
• Normalization
• RDBMS

3. SQL EXAMPLES

4. RDBMS BENEFITS
• Normalization (a common
standard format for
accessing data)
• Data consistency
• Persistence
• Consistency
• Replication

5. RDBMS PROBLEMS

6. RDBMS PROBLEMS
• Highcost on performing
complex operations over a
big database
• High
system load: scalability
needs
• Difficult failover recovery
• Difficult denormalization

7. NOSQL TO THE RESCUE!

8. NOSQL IS...
•A storage system for format
free data
• Web scale
• Software darwinism
• Different
types of solutions
depending on the needs:
Key-value, Documents,
Graphs, Objects...

9. REDIS
• http://redis.io Redis is SEXY
• Key-value store
• In memory
• Persistent
(periodical
asynchronous writes to disk)
• All operations are atomic

10. REDIS
Types of data Cool operations
• Hashes
• RPOPLPUSH
• Sets (arrays)
• Pub/Sub
• Lists

11. REDIS
HSET myuser “email” “ivan@ivanhq.net”
HSET myuser “web” “http://ibelmonte.com”
HSET myuser “blog” “http://ivanh.net”
HGET myuser “email”
- ivan@ivanhq.net

12. REDIS
sadd myuser:books “jackass”
sadd myuser:books “jackass2”
sadd myuser:books “Dude, where’s my car?”
sadd myuser:books “The hangover”
smembers myuser:books
1. jackass
2. jackass2
3. Dude, where’s my car?
4. The hangover

13. REDIS
rpush friends “John Doe”
rpush friends “Foo”
rpush friends “Bar”
lrange friends 0 -1
1. John Doe
2. Foo
3. Bar

14. REDIS
rpush nonfriends “Peter Pan”
rpush nonfriends “Batman”
rpush nonfriends “Betty Boop”
lrange nonfriends 0 -1
1. Peter Pan
2. Batman
3. Betty Boop

15. REDIS
rpoplpush nonfriends friends
lrange friends 0 -1
1. John Doe
2. Foo
3. Bar
4. Betty Boop
lrange nonfriends 0 -1
1. Peter Pan
2. Batman

16. REDIS
Pub/Sub.... a freaking AWESOME messaging queue

17. REDIS
Pro’s:
- Highly performant
- Highly scalable
- Interfaces available for many languages (Ruby: Ohm)
Cons:
- Eats your server’s memory
- Manually sharding

18. MONGODB
• http://mongodb.org
• Document store
• Writes to disk
• Hight scalability
• Easy sharding

19. MONGODB
• Organizes data using
collections
• Stores documents in BSON
format, a binary-encoded
serialization of JSON

20. MONGODB
use users
u = { name: “ivan”, company: “Sysdivision”, age: “32” }
users.insert(u)
users.find();
- { "_id" : ObjectId("4d5ea4e79faeda067681e214"),
"name" : "ivan", company: “Sysdivision”, "age" : "32" }

21. MONGODB
use users
u = { name: “ivan”, company: “Sysdivision”, age: “32” }
users.insert(u)
db.users.find({name: “ivan”});
- { "_id" : ObjectId("4d5ea4e79faeda067681e214"),
"name" : "ivan", company: “Sysdivision”, "age" : "32" }
db.users.find();
db.users.find().skip(20).limit(10);

22. MONGOID
class User
include Mongoid::Document
field :name
field :birthday, :type => date
field :money, :type => float, :default => 0.0
embedded_in :company
end
class Company
field :name
embeds_one :user
end

23. MONGOID
company = Company.create(:name => ‘Sysdivision’)
company.create_user(
:name => ‘John Doe’,
:birthday => ’12/7/1982’,
: money => 0
)
User.find(:name => ‘John Doe’)
User.where(:name => /.*ohn.*/)

24. MONGOID
User.any_of(
{ :name => ‘John Doe’ },
{ :money.gt 10 }
)
User.any_in(:name => [‘John’, ‘Foo’, ‘Bar’])
User.where(:name => ‘John Doe’).and(:money.gt 10)
Post.all_in(:tags => [‘ruby’, ‘code’, ‘mongo’])

25. MONGODB
Pro’s:
- Highly performant
- Highly scalable
- Easy sharding
- Ultra powerful querying
- Interfaces available for many languages (Ruby:
mongo_mapper, mongoid)

26. NOSQL AWESOMENESS

27. QUESTIONS?
Ivan Belmonte
http://ibelmonte.com
ivan@ivanhq.net