SELECT vrevisions.for_vrevisions('
    UPDATE objects_a7 SET part=NULL;
    UPDATE objects_a8 SET part=NULL;
    UPDATE objects_a10 SET part=NULL;
    UPDATE objects_a12 SET part=NULL;
    UPDATE objects_a14 SET part=NULL;

    UPDATE objects_a16 SET part=NULL;
    DROP TABLE objects_a16;
');
