759         restrictions, tables = self._state.pop_scope()

   759         restrictions, tables = self._state.pop_scope()

   760         if restriction:

   760         if restriction:

   761             restrictions.append(restriction)

   761             restrictions.append(restriction)

   762         restriction = ' AND '.join(restrictions)

   762         restriction = ' AND '.join(restrictions)

   763         if not restriction:

   763         if not restriction:

   764             return ''

   766             return ''

   765         if not tables:

   767         if not tables:

   766             # XXX could leave surrounding EXISTS() in this case no?

   768             # XXX could leave surrounding EXISTS() in this case no?

   767             sql = 'SELECT 1 WHERE %s' % restriction

   769             sql = 'SELECT 1 WHERE %s' % restriction

   768         else:

   770         else: