﻿update oo
set oo.C_FOGLALKOZASID = NULL
from T_ORARENDIORA oo
inner join T_FOGLALKOZAS f on f.ID = oo.C_FOGLALKOZASID and f.TOROLT = 'F'
where oo.TOROLT = 'F'
  and oo.C_TANARID <> f.C_TANARID