My talk about Sequel @ Madrid Ruby user group

1. Fernando Blat
@ferblape
Tuesday, April 12, 2011

2. Un poco sobre mí
• De Valencia • unvlog.com
• 4 años en The Cocktail y • iwannagothere.com //
La Coctelera mimaleta.com
• He sido freelance un • lacoctelera.com //
tiempo partigi.com
• Ahora trabajo en • actuable.es
Vizzuality
Tuesday, April 12, 2011

3. Sequel!
Tuesday, April 12, 2011

4. Dataset
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5. Representación de un
conjunto de filas de una
o varias tablas
Tuesday, April 12, 2011

6. users updates
- id - id
- username - user_id
- email - message
- created_at - created_at
Tuesday, April 12, 2011

7. DB = Sequel.connect('sqlite://
ddbb.sqlite3')
DB.class
=> Sequel::Postgres::Database
Tuesday, April 12, 2011

8. users = DB[:users]
=> #<Sequel::SQLite::Dataset:
"SELECT * FROM `users`">
Tuesday, April 12, 2011

9. users.filter("email = ?", 'ferblape@gmail.com')
=> #<Sequel::SQLite::Dataset: "SELECT * FROM
`users` WHERE (email = 'ferblape@gmail.com')">
Tuesday, April 12, 2011

10. users.filter("email = ?", 'ferblape@gmail.com').sql
=> "SELECT * FROM `users` WHERE (email =
'ferblape@gmail.com')
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11. Un Dataset es una
representación
Tuesday, April 12, 2011

12. #first, #last,
#count,
#all, ...
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13. Algunas consultas con
Sequel
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14. users[1]
users[:username => 'blat']
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15. users.filter({:email =>
['ferblape@gmail.com','ferblape@vizzuality.co
m']}).sql
=> "SELECT * FROM `users` WHERE (`email` IN
('ferblape@gmail.com',
'ferblape@vizzuality.com'))"
Tuesday, April 12, 2011

16. users.filter({:email =>
['ferblape@gmail.com','ferblape@vizzuality.co
m']} & ~{:username => 'blat'}).sql
=> "SELECT * FROM `users` WHERE ((`email` IN
('ferblape@gmail.com',
'ferblape@vizzuality.com')) AND (`username` !
= 'blat'))"
Tuesday, April 12, 2011

17. users.filter{created_at > Date.today}.or
{created_at < Date.today - 60}.order
(:id).limit(10).sql
=> "SELECT * FROM `users` WHERE
((`created_at` > '2011-03-26') OR
(`created_at` < '2011-01-25')) ORDER BY `id`
LIMIT 10"
Tuesday, April 12, 2011

18. Inserciones
Tuesday, April 12, 2011

19. users.insert(:username => 'blat', :email =>
'ferblape@gmail.com')
=> 1
users.insert(:username => 'blatvizz', :email
=> 'ferblape@vizzuality.com')
=> 2
Tuesday, April 12, 2011

20. Actualizaciones
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21. users.update(:id => :id + 1000)
=> 2
users.all
=>
[{:id=>1001, :username=>"blat",
:email=>"ferblape@gmail.com",
:created_at=>2011-03-26 00:00:00 +0100},
{:id=>1002, :username=>"blatvizz",
:email=>"ferblape@vizzuality.com",
:created_at=>2011-03-26 00:00:00 +0100}]
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22. Resultados de las
consultas
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23. users.all
=>
[{:id=>1, :username=>"blat",
:email=>"ferblape@gmail.com",
:created_at=>nil},
{:id=>2, :username=>"blatvizz",
:email=>"ferblape@vizzuality.com",
:created_at=>nil}]
Tuesday, April 12, 2011

24. users.to_hash(:id,:username)
=> {1=>"blat", 2=>"blatvizz"}
Tuesday, April 12, 2011

25. users.select_map(:username)
=> ["blat", "blatvizz"]
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26. Algunos ejemplos más
esotéricos
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27. users.group_and_count(:id).sql
=> "SELECT `id`, count(*) AS 'count'
FROM `users` GROUP BY `id`"
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28. updates.join(users.filter{created_at <
Date.today}, :id => :user_id).sql
=> "SELECT * FROM `updates` INNER JOIN
(SELECT * FROM `users` WHERE (`created_at` <
'2011-03-26')) AS 't1' ON (`t1`.`id` =
`updates`.`user_id`)"
Tuesday, April 12, 2011

29. users.select(:username___wadus).sql
=> "SELECT `username` AS 'wadus' FROM
`users`"
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30. Modelos
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31. Tuesday, April 12, 2011

32. class Table < Sequel::Model(:user_tables)
# Ignore mass-asigment on not allowed columns
self.strict_param_setting = false
# Allowed columns
set_allowed_columns(:name, :privacy, :tags)
def before_validation
self.privacy ||= :public
self.name = set_table_name if self.name.blank?
super
end
...
end
Tuesday, April 12, 2011

33. Más
Tuesday, April 12, 2011

34. • migraciones estilo • zonas horarias
ActiveRecord
• relaciones
• gestión de múltiples • dirty attributes
bbdd: maestro-esclavo,
maestro-maestro • serialización JSON
• sharding de tablas • compatibilidad con
ActiveModel
• transacciones
• paginación • extensiones y plugins
Tuesday, April 12, 2011

35. Tuesday, April 12, 2011

36. ¿Vale la pena utilizarlo
con Rails?
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37. Acoplamiento
• tareas Rake
• migraciones
• generadores
• config/database.yml
Tuesday, April 12, 2011

38. sequel-rails
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39. Gracias!
Tuesday, April 12, 2011