Couple good old usefull Rails ActiveRecord's methods

posted on Tuesday, June 29, 2010

This will increment "views" attribute of the post and save it to database, increment!(attribute, by=1):

@post.increment!(:views)

This will decrement "views" attribute of the post and save it to database, decrement!(attribute, by=1):

@post.decrement!(:views)

This will assign to attribute the boolean opposite of it:

@post.published # -> true
@post.toggle!(:published)
@post.published # -> false

class PostsController < ApplicationController
  before_filter :find_post, :only => [:publish, :show]
  def show
    @post.increment!(:views)
  end
  private
    def find_post
      @post = Post.find(params[:id])
    end
end

Reloading attributes from database, to get the latest values, reload(options = nil):

@post = user.posts.find(5)
user.posts.find(5).increment!(:views)
@post.views # -> 0
@post.reload
@post.views # -> 1

Reordering of already defined scope:

Post.scoped.collect {|p| p.id }
- 1
- 2
- 3

Post.scoped.reverse_order.collect {|p| p.id }
- 3
- 2
- 1