rails/rails — pull request #6920 by lexmag (2012-07-01 14:18:33+00:00)
Title: Reference statements

Add references schema statements.

Examples:

add_reference :products, :supplier, polymorphic: true, index: true
remove_reference :products, :supplier

`add_belongs_to`, `remove_reference` and `remove_references` are
acceptable. `add_reference` is reversible.

Relies on #6914