PHP - Tabla dinamica filtrada por meses

<form action= "index.php" class="formulario"

    enctype="multipart/form-data" method="post">

    <select name="DIAS">

        <option value="DIA">DIA</option>

        <option value="DIA-1">DIA-1</option>

    </select>

labels : [

    <?php

    if (isset($_POST['DIAS'])){

      if ($_POST['DIAS']='DIA') {

          $gra1= ("SELECT * from (select sum(contador) TOTAL ,DEFECTO ,FECHA from (select 1 'contador',DEFECTO ,FECHA from part_historico_lin where DEFECTO is not null and DEFECTO != '') t group by DEFECTO ) t1 ORDER BY `t1`.`TOTAL` ASC limit 1");

          }  else if ($_POST['DIAS']='DIA-1') {

            $gra1= ("SELECT * from (select sum(contador) TOTAL ,DEFECTO ,FECHA from (select 1 'contador',DEFECTO ,FECHA from part_historico_lin where DEFECTO is not null and DEFECTO != '') t group by DEFECTO ) t1 ORDER BY `t1`.`TOTAL` ASC limit 2");

          }  else {

            $gra1= ("SELECT * from (select sum(contador) TOTAL ,DEFECTO ,FECHA from (select 1 'contador',DEFECTO ,FECHA from part_historico_lin where DEFECTO is not null and DEFECTO != '') t group by DEFECTO ) t1 ORDER BY `t1`.`TOTAL` ASC limit 3");

          }

          $gra1= ("SELECT * from (select sum(contador) TOTAL ,DEFECTO ,FECHA from (select 1 'contador',DEFECTO ,FECHA from part_historico_lin where DEFECTO is not null and DEFECTO != '') t group by DEFECTO ) t1 ORDER BY `t1`.`TOTAL` ASC limit 3");

          }

   //$gra1= ("SELECT * from (select sum(contador) TOTAL ,DEFECTO ,FECHA from (select 1 'contador',DEFECTO ,FECHA from part_historico_lin where DEFECTO is not null and DEFECTO != '') t group by DEFECTO ) t1 ORDER BY `t1`.`TOTAL` ASC limit 1");

  //  $gra2= ("SELECT * from (select sum(contador) TOTAL ,DEFECTO ,FECHA from (select 1 'contador',DEFECTO ,FECHA from part_historico_lin where DEFECTO is not null and DEFECTO != '') t group by DEFECTO ) t1 ORDER BY `t1`.`TOTAL` ASC limit 2");

    $resultado2=$enlace->query($gra1);

    while($gra1 = mysqli_fetch_array($resultado2)){

?>

'<?php echo $gra1['DEFECTO'] ?>',

<?php

}

?>

],