[ecfisa]

Hola fjcg02.

Fijate si este ejemplo se parece a lo que estas buscando,

Código Delphi [-]
// Crear columna
procedure CrearColumna(ClientDataSet: TClientDataSet; const FieldName: string;
  const FieldType: TFieldType; const FieldSize: Integer = 0);
begin
  with ClientDataSet do
  begin
    with FieldDefs.AddFieldDef do
    begin
      DataType := FieldType;
      Name     := FieldName;
      //...
      if FieldSize > 0 then Size := FieldSize;
    end;
  end;
end;

// Crear unas columnas y cargar (1)
procedure TForm1.Button1Click(Sender: TObject);
var
  i: Integer;
begin
  with ClientDataSet1 do
  begin
    Close;
    FieldDefs.Clear;
    CrearColumna(ClientDataSet1, 'Integer', ftInteger);
    CrearColumna(ClientDataSet1, 'String', ftString, 30);
    CrearColumna(ClientDataSet1, 'Float', ftFloat);
    CreateDataSet;
    Open;
    for i:= 1 to 1000 do
    begin
      Append;
      FieldByName('Integer').AsInteger := i;
      FieldByName('String').AsString   := 'Valor '+IntToStr(i);
      FieldByName('Float').AsFloat     := PI * i;
      Post;
    end;
    First;
  end;
end;

// Crear unas columnas y cargar (2)
procedure TForm1.Button2Click(Sender: TObject);
var
  i: Integer;
begin
  with ClientDataSet1 do
  begin
    Close;
    FieldDefs.Clear;
    CrearColumna(ClientDataSet1, 'String', ftString, 15);
    CrearColumna(ClientDataSet1, 'DateTime', ftDateTime);
    CrearColumna(ClientDataSet1, 'Currency', ftCurrency);
    CreateDataSet;
    Open;
    for i:= 1 to 1000 do
    begin
      Append;
      FieldByName('String').AsString     := 'Valor '+IntToStr(i);
      FieldByName('DateTime').AsDateTime := Now();
      FieldByName('Currency').AsFloat    := PI * i;
      Post;
    end;
    First;
  end;
end;

Saludos

Edito: Perdón fjcg02, no ví tu último mensaje mientras tenía este abierto.