def wrap(prefix = name.dataset)
      new(map { |attr| attr.wrapped? ? attr : attr.wrapped(prefix) })
    end
def wrap(prefix = name.dataset)
      new(map { |attr| attr.wrapped? ? attr : attr.wrapped(prefix) })
    end
Return new schema with all attributes marked as prefixed and wrapped

 This is useful when relations are joined and the right side should be marked
 as wrapped

 @param [Symbol] prefix The prefix used for aliasing wrapped attributes

 @return [Schema]

 @api public