with form1.ADOQuery1 do
begin
 Close;
 SQL.Clear;
 SQL.Add('Select TOP 3 ab4.TV as TV, ab4.SM1 as SM1,ab4.SM2 as SM2, ab4.Y as Y');
 SQL.Add('FROM');
 SQL.Add(' (Select TV1 AS TV, SUM(summa1) as SM1, 0 as SM2, y1 AS Y from table_1');
 SQL.Add('Union all');
 SQL.Add('Select TV2 AS TV, 0 as SM1, SUM(summa2) as SM2, y2 AS Y from table_2) ab4');
 SQL.Add('group by ab4.TV');
 SQL.Add('order by ab4.SM2 desc ');
 open;
end;
 
 x:=form1.ADOQuery1. //выбрать вторую ячейку
Showmessage(floattoSTR(x));

dm3.adoquery1.RecNo:=2;
x:=dm3.adoquery1.FieldByName('summa2').Asstring;
showmessage(X);