[NumLock]

Код:

var
  FldLst: String;
begin
  FldLst:='';
  if CheckBox1.Checked then FldLst:=FldLst+', Chann01';
  if CheckBox2.Checked then FldLst:=FldLst+', Chann02';
  if CheckBox3.Checked then FldLst:=FldLst+', Chann03';
  if CheckBox4.Checked then FldLst:=FldLst+', Chann04';
  Query1.SQL.Text:='SELECT SimpleTime'+FldLst+' FROM RGBTEC4.dbo.Data_25010_4_0_8  where SimpleTime between :Param1 and :Param2';
end;