@rohitpaulk the `t.references` call is not very magical. It simply appends `_id` to the reference name you give it. Since the association is called `manager`, the foreign key will be `manager_id`. Hence it should be `t.references :manager`

see https://github.com/rails/rails/blob/master/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb#L622-L623