#202 Active Record Queries in Rails 3

Feb 22, 2010 | 10 minutes | Active Record, Rails 3.0

Rails 3 introduces a new query interface for performing finds in Active Record. See how it works along with the changes in named scopes.

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          ruby
        
# Article.find(:all, :order => "published_at desc", :limit => 10)
Article.order("published_at desc").limit(10)

# Article.find(:all, :conditions => ["published_at <= ?", Time.now], :include => :comments)
Article.where("published_at <= ?", Time.now).includes(:comments)

# Article.find(:first, :order => "published_at desc")
Article.order("published_at").last

          rails console
        
Article.all
articles = Article.order("name")
articles.all
articles.first
Article.recent.all
puts Article.recent.to_sql

          articles_controller.rb
        
@articles = Article.order("name")

if params[:hidden]
  @articles = @articles.where(:hidden => (params[:hidden] == "1"))
end

          models/active_record.rb
        
scope :visible, where("hidden != ?", true)
scope :published, lambda { where("published_at <= ?", Time.zone.now) }
scope :recent, visible.published.order("published_at desc")