         field :field_name_hash, Cloak.SHA256Field
       end
 
-  You'll also want to add `before_insert/1` and `before_update/1` callbacks to
+  In versions of Ecto < 2.0 you'll also want to add `before_insert/1` and `before_update/1` callbacks to
   ensure that the field is set every time that `:field_name` changes.
 
       before_insert :set_field_name_hash

      defp set_field_name_hash(changeset) do
        put_change(changeset, :field_name_hash, get_field(changeset, :field_name))
      end
  """

  @doc false


  ## Usage

  By storing a hash of a field's value, you can then query on it as a proxy 
  for the encrypted field because SHA256 is deterministic and always results 
  in the same value, whereas secure encryption does not. Be warned, however, 
  that this will expose fields which have the same value, because they will 
  contain the same hash.

  You should create the hash field with the type `:binary`. It can then be added to
  your `schema` definition like this:

      schema "table" do
