Thank for your answer mangakissa
My first problem is that all the rows are populated, even if I used "GROUP BY"
When I access the first: SQLQuery1.Fields[0].asstring;
I am expecting that the second one, to be empty, unless there is a new value, but not. The field (and the others) are always populated, even if there is no change!
I try to not add the "GROUP BY" fields in my "SELECT", but they are not showned at all then!
Best Regards
Jean-Christophe