I would like to thank you for immediate answers. I tryed the solution you
have written and it gives me strange results.
In the place of A.barcode I get all barcodes from all shops. The
B.barcodeis fine I think because it gives me just those from shop 2
and nulls.
I think I will create procedure which gets me all distinct barcodes from
shops table and left join it with shops table. Maybe it will work. It
should.
But the guys from firebird-devel should check this strange problem.

All the best,
Damir


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