module ActiveRecord::SpawnMethods - activerecord-4.2.4 Documentation

# module ActiveRecord::SpawnMethods

### Public Instance Methods

except(*skips) click to toggle source

Removes from the query the condition(s) specified in `skips`.

    Post.order('id asc').except(:order)                  # discards the order condition
    Post.where('id > 10').order('id asc').except(:where) # discards the where condition but keeps the order

    # File lib/active_record/relation/spawn_methods.rb, line 52
    def except(*skips)
      relation_with values.except(*skips)
    end

merge(other) click to toggle source

Merges in the conditions from `other`, if `other` is an `ActiveRecord::Relation`. Returns an array representing the intersection of the resulting records with `other`, if `other` is an array.

    Post.where(published: true).joins(:comments).merge( Comment.where(spam: false) )
    # Performs a single join query with both where conditions.

    recent_posts = Post.order('created_at DESC').first(5)
    Post.where(published: true).merge(recent_posts)
    # Returns the intersection of all published posts with the 5 most recently created posts.
    # (This is just an example. You'd probably want to do this with a single query!)

Procs will be evaluated by merge:

    Post.where(published: true).merge(-> { joins(:comments) })
    # => Post.where(published: true).joins(:comments)

This is mainly intended for sharing common conditions between multiple associations.

    # File lib/active_record/relation/spawn_methods.rb, line 29
    def merge(other)
      if other.is_a?(Array)
        to_a & other
      elsif other
        spawn.merge!(other)
      else
        self
      end
    end

only(*onlies) click to toggle source

Removes any condition from the query other than the one(s) specified in `onlies`.

    Post.order('id asc').only(:where)         # discards the order condition
    Post.order('id asc').only(:where, :order) # uses the specified order

    # File lib/active_record/relation/spawn_methods.rb, line 60
    def only(*onlies)
      if onlies.any? { |o| o == :where }
        onlies << :bind
      end
      relation_with values.slice(*onlies)
    end