def setOrderHook(self, hook):
		"""
			Installs *hook* as a callback function for new orderings.

			*hook* will be called each time a :func:`db.Query.order` is called on this query.

			:param hook: The function to register as callback. \
			A value of None removes the currently active hook.
			:type hook: callable

			:returns: The previously registered hook (if any), or None.
		"""
		old = self._orderHook
		self._orderHook = hook
		return( old )