def _put_into_indexes(self, obj):
        """
        Put publication into all indexes.

        Attr:
            obj (obj): Indexable object.

        Raises:
            UnindexableObject: When there is no index (property) which can be
                used to index `obj` in database.
        """
        no_of_used_indexes = 0
        for field_name, db_index in list(self._get_db_fields(obj)):
            attr_value = getattr(obj, field_name)

            if attr_value is None:  # index only by set attributes
                continue

            container = db_index.get(attr_value, None)
            if container is None:
                container = OOTreeSet()
                db_index[attr_value] = container

            container.insert(obj)

            no_of_used_indexes += 1

        # make sure that atleast one `attr_value` was used
        if no_of_used_indexes <= 0:
            raise UnindexableObject(
                "You have to use atleast one of the identificators!"
            )
Put publication into all indexes.

        Attr:
            obj (obj): Indexable object.

        Raises:
            UnindexableObject: When there is no index (property) which can be
                used to index `obj` in database.