Oye....no haría falta en esta parte del código...el POST para ambos DataSets??
Código Delphi
[-]procedure TForm1.Button1Click(Sender: TObject);
begin
DM.tbMaster.Append;
DM.tbMaster.FieldByName('ID').AsInteger := 5;
DM.tbMaster.FieldByName('TEXT').AsString := 'ROW 5';
DM.tbDetail.Append;
DM.tbDetail.FieldByName('ID').AsInteger := 6;
DM.tbDetail.FieldByName('TEXT').AsString := '';
DM.tbDetail.FieldByName('MAESTRO_ID').AsInteger := 5;
DM.tbDetail.DataSource := nil;
try
DM.IBDatabase1.ApplyUpdates([DM.tbMaster, DM.tbDetail]);
finally
DM.tbDetail.DataSource := DM.dsMaster;
end;
end;