method

chain

Ruby on Rails latest stable (v6.1.7.7) - 0 notes - Class: ActiveRecord::Reflection::ThroughReflection

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What's this?

Method deprecated or moved

This method is deprecated or moved on the latest stable version. The last existing version (v4.2.9) is shown here.

These similar methods exist in v6.1.7.7:

ActiveRecord::Reflection::AbstractReflection#chain

chain() public

Returns an array of reflections which are involved in this association. Each item in the array corresponds to a table which will be part of the query for this association.

The chain is built by recursively calling #chain on the source reflection and the through reflection. The base case for the recursion is a normal association, which just returns

self: as its #chain.

class Post < ActiveRecord::Base
  has_many :taggings
  has_many :tags, through: :taggings
end

tags_reflection = Post.reflect_on_association(:tags)
tags_reflection.chain
# => [<ActiveRecord::Reflection::ThroughReflection: @delegate_reflection=#<ActiveRecord::Reflection::HasManyReflection: @name=:tags...>,
      <ActiveRecord::Reflection::HasManyReflection: @name=:taggings, @options={}, @active_record=Post>]

Show source

# File activerecord/lib/active_record/reflection.rb, line 707
      def chain
        @chain ||= begin
          a = source_reflection.chain
          b = through_reflection.chain
          chain = a + b
          chain[0] = self # Use self so we don't lose the information from :source_type
          chain
        end
      end

chain

Related methods

Method deprecated or moved

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