> Pasitaisau shiek tiek, turetu buti:
>>      (INV1.datephysical >='2011.07.01' or INV1.datephysical IS NULL)  and
>>      (INV1.datephysical <='2011.07.31' or INV1.datephysical IS NULL)  and
>>      (LIK1.DATEPHYSICAL >= '2011.07.01' or LIK1.datephysical IS NULL) and
>>      (LIK1.DATEPHYSICAL <= '2011.07.31' or LIK1.datephysical IS NULL)

  OK bandysiu . Tiesa , jeigu naudot Isnull() funkcija , tuomet group by 
keikiasi . Su case viskas eina .