Hi,

here the plan:

Plan
PLAN JOIN (JOIN (Q X ORDER PK_ROBFAKTURA, Q Y INDEX
(FK_ROBFAKTURAS_1)), Z INDEX (PK_ROBFAKTURA))

Adapted Plan
PLAN JOIN (JOIN (Q X ORDER PK_ROBFAKTURA, Q Y INDEX
(FK_ROBFAKTURAS_1)), Z INDEX (PK_ROBFAKTURA))

I'm using IBExpert for DB development and UIB for application
development. I think that is a lillte closer look on my problem!

Thnaks again...