john, stuart, some_plz, 123456, 234557
    tel49, vorname, tel, plz, name are good
john, stuart, some_plz, 123456,
    vorname, tel, plz, name are good
john, stuart, some_plz,, 234557
    tel49, vorname, plz, name are good
, stuart, , 123456, 234557
    tel49, vorname, tel are good
, , , , 234557
    tel49 is good
,,,,
    No variables are good