Rails >= 3.2(包括Rails 4+和5+):

class Countries < ActiveRecord::Base
  self.table_name = "cc"
end

Rails <= 3.1:

class Countries < ActiveRecord::Base
  self.set_table_name "cc"
  ...
end

class Countries < ActiveRecord::Base
    self.table_name = "cc"
end

在Rails 3中。这是指定表名的方法。