este es el codigo completo que le paso al query
Código Delphi
[-]
with datamodule29.Query2 do
Begin
Close;
SQl.Clear;
SQL.Add('Select idmes from mes where mes=
mes');
ParamByName('pmes').AsString:=suiDBLookupComboBox2.Text;
Open;
mes:=FieldByName('idmes').AsInteger;
Close;
SQl.Clear;
SQL.Add('Select * from mes where idmes=
idmes');
ParamByName('pidmes').AsInteger:=mes;
Open;
inicio:=FieldByName('inicio').AsString;
fin:=FieldByName('fin').AsString;
Close;
SQL.Clear;
SQL.Add('SELECT C.IDCARRO, C.NOCARRO, C.INDICECONS, SUM(DHR.KMRECORRIDO), SUM(CO.CONSUMO)');
SQL.Add('FROM CARRO C INNER JOIN HOJARUTA HR ON HR.IDCARRO = C.IDCARRO');
SQL.Add('INNER JOIN DESCHOJARUTA DHR ON DHR.IDHOJARUTA = HR.IDHOJARUTA');
SQl.Add('INNER JOIN CONSUMO CO ON CO.IDCARRO = C.IDCARRO');
SQL.Add('WHERE CO.FECHA BETWEEN :FECHA1 AND :FECHA2');
SQL.Add('GROUP BY C.IDCARRO, C.NOCARRO, C.INDICECONS');
SQL.Add('ORDER BY C.IDCARRO');
ParamByName('FECHA1').AsString:=inicio;
ParamByName('FECHA2').AsString:=fin;
Open;
end;