Instance Public methods

Returns a scope for the model without the previously set scopes.

class Post < ActiveRecord::Base
  def self.default_scope
    where(published: true)

Post.all                                  # Fires "SELECT * FROM posts WHERE published = true"
Post.unscoped.all                         # Fires "SELECT * FROM posts"
Post.where(published: false).unscoped.all # Fires "SELECT * FROM posts"

This method also accepts a block. All queries inside the block will not use the previously set scopes.

Post.unscoped {
  Post.limit(10) # Fires "SELECT * FROM posts LIMIT 10"
# File activerecord/lib/active_record/scoping/default.rb, line 34
def unscoped
  block_given? ? relation.scoping { yield } : relation
Instance Private methods
default_scope(scope = nil)

Use this macro in your model to set a default scope for all operations on the model.

class Article < ActiveRecord::Base
  default_scope { where(published: true) }

Article.all # => SELECT * FROM articles WHERE published = true

The default_scope is also applied while creating/building a record. It is not applied while updating a record.    # => true
Article.create.published # => true

(You can also pass any object which responds to call to the default_scope macro, and it will be called when building the default scope.)

If you use multiple default_scope declarations in your model then they will be merged together:

class Article < ActiveRecord::Base
  default_scope { where(published: true) }
  default_scope { where(rating: 'G') }

Article.all # => SELECT * FROM articles WHERE published = true AND rating = 'G'

This is also the case with inheritance and module includes where the parent or module defines a default_scope and the child or including class defines a second one.

If you need to do more complex things with a default scope, you can alternatively define it as a class method:

class Article < ActiveRecord::Base
  def self.default_scope
    # Should return a scope, you can call 'super' here etc.
# File activerecord/lib/active_record/scoping/default.rb, line 90
def default_scope(scope = nil) # :doc:
  scope = if block_given?

  if scope.is_a?(Relation) || !scope.respond_to?(:call)
    raise ArgumentError,
      "Support for calling #default_scope without a block is removed. For example instead "                  "of `default_scope where(color: 'red')`, please use "                  "`default_scope { where(color: 'red') }`. (Alternatively you can just redefine "                  "self.default_scope.)"

  self.default_scopes += [scope]