rails. Active Record. Associations?

Question

Ruby on Rails

There is an Images table. How to properly associate Images to itself using migrations? How to correctly name the additional linking table? What to register in the Image model?

Answer 1

Everything, now I understand.
You create the table image_diff (for example).
fields: image_id, second_image_id, percent
Class ImageDiff:
belongs_to :image
belongs_to :second_image, :class_name => "Image", :foreign_key => "second_image_id"
Class Image:
has_one :image_diff # one-to-one relationship because first_image_id binds to the Image model
and it will be possible to access:
im = Image.first
im.image_diff.percent
im.image_diff.second_image # here it will display all the links, so you will need to iterate over them one by one