console usage without inverse_of

console.rb

post = Post.first
=> #<Post id: 1, title: "First post">

comment = post.comments.first
=> #<Comment id: 1, body: "I agree!", post_id: 1>

# Changing the post title in memory
post.title = "First post - revised"

post.title
=> "First post - revised"

comment.post.title
=> "First post"

# They are in fact the same object...

post == comment.post
=> true

# ...but different in-memory objects

post.title == comment.post.title
=> false

post.object_id
=> 70135767956700
comment.post.object_id
=> 70135784070660