Method select_for_update

django/db/models/query.py:1740–1754

Return a new QuerySet instance that will select objects with a FOR UPDATE lock.

(self, nowait=False, skip_locked=False, of=(), no_key=False)

        return self._combinator_query("difference", *other_qs)

    def select_for_update(self, nowait=False, skip_locked=False, of=(), no_key=False):
        """
        Return a new QuerySet instance that will select objects with a
        FOR UPDATE lock.
        """
        if nowait and skip_locked:
            raise ValueError("The nowait option cannot be used with skip_locked.")
        obj = self._chain()
        obj._for_write = True
        obj.query.select_for_update = True
        obj.query.select_for_update_nowait = nowait
        obj.query.select_for_update_skip_locked = skip_locked
        obj.query.select_for_update_of = of
        obj.query.select_for_no_key_update = no_key
        return obj

    def select_related(self, *fields):
        """