Rails migration: t.references with alternative name?

Question

So I have a create_table like this for Courses at a School:

create_table :courses do |t|
  t.string :name
  t.references :course
  t.timestamps
end

Answer 1

You can do it this way:

create_table :courses do |t|
  t.string :name
  t.references :transferrable_as
  t.references :same_as
  t.timestamps
end

or using t.belongs_to as an alias for t.references

You can't add foreign_key: true to those two references lines. If you want to mark them as foreign keys at the database level you need to have a migration with this:

add_foreign_key :courses, :courses, column: :transferrable_as_id
add_foreign_key :courses, :courses, column: :same_as_id

Update

In Rails 5.1 and above you can add the foreign key in the migration in the create_table block like this:

create_table :courses do |t|
  t.string :name
  t.references :transferrable_as, foreign_key: { to_table: 'courses' }
  t.references :same_as, foreign_key: { to_table: 'courses' }
  t.timestamps
end