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![users = DB[:users]
=> #<Sequel::SQLite::Dataset:
"SELECT * FROM `users`">
Tuesday, April 12, 2011](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-8-2048.jpg)
![users[1]
users[:username => 'blat']
Tuesday, April 12, 2011](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-14-2048.jpg)
![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](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-15-2048.jpg)
![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](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-16-2048.jpg)
![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}]
Tuesday, April 12, 2011](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-21-2048.jpg)
![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](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-23-2048.jpg)
![users.select_map(:username)
=> ["blat", "blatvizz"]
Tuesday, April 12, 2011](https://image.slidesharecdn.com/sequel-madrid-rb-110412022136-phpapp01/75/Sequel-madrid-rb-25-2048.jpg)
Uploaded byFernando Blat
Sequel @ madrid-rb
Fernando Blat gives an overview of himself and his work experience. He then provides a detailed presentation on using the Sequel gem to perform queries, inserts, updates and more on SQLite databases from Ruby. Sequel allows representing database tables as objects and chaining SQL methods to build queries in a Rubyistic way. Models can also be defined using Sequel to map rows to objects.
![Vibe Coding vs. Spec-Driven Development [Free Meetup]](https://cdn.slidesharecdn.com/ss_thumbnails/vibecodingvsspecdrivendevelopment-251209105622-43f455e7-thumbnail.jpg?width=640&height=640&fit=bounds)
Sequel @ madrid-rb
- 1. Fernando Blat @ferblape Tuesday, April 12, 2011
- 2. Un poco sobremí • 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.
- 4.
- 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') Tuesday, April 12, 2011
- 11. Un Dataset esuna representación Tuesday, April 12, 2011
- 12. #first, #last, #count, #all, ... Tuesday, April 12, 2011
- 13. Algunas consultas con Sequel Tuesday, April 12, 2011
- 14. users[1] users[:username => 'blat'] Tuesday, April 12, 2011
- 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.
- 19. users.insert(:username => 'blat',:email => 'ferblape@gmail.com') => 1 users.insert(:username => 'blatvizz', :email => 'ferblape@vizzuality.com') => 2 Tuesday, April 12, 2011
- 20.
- 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}] Tuesday, April 12, 2011
- 22. Resultados de las consultas Tuesday, April 12, 2011
- 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"] Tuesday, April 12, 2011
- 26. Algunos ejemplos más esotéricos Tuesday, April 12, 2011
- 27. users.group_and_count(:id).sql => "SELECT `id`, count(*) AS 'count' FROM `users` GROUP BY `id`" Tuesday, April 12, 2011
- 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`" Tuesday, April 12, 2011
- 30.
- 31.
- 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.
- 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.
- 36. ¿Vale la penautilizarlo con Rails? Tuesday, April 12, 2011
- 37. Acoplamiento • tareas Rake • migraciones • generadores • config/database.yml Tuesday, April 12, 2011
- 38.
- 39.