从php后端每隔n秒刷新多个类

Question

我在jquery中有一些连接到php并用最新数据刷新类的代码。这工作正常。但是，我需要更新3个类，当它刷新时，值为空。

有没有办法可以每隔n秒查询数据库并用新数据更新3个类。非常感谢

JS

// Update server with latest actions,destructions and return requests
    setInterval(function() {
      $.get('/domain/admin/refreshBox.php', function(data) {
      $(".actions").text(data);
      $(".retrievals").text(data);
      $(".returns").text(data);
      });
    }, 10000);

PHP

$sql= mysqli_query($conn,"SELECT count(*) as total FROM act WHERE new = '1'");
    $rows = mysqli_fetch_assoc($sql);
    $num = $rows['total'];
    //echo $num;
    $ni = $num;

    if($ni < 1) {
      $ni = '0';
    }
    echo $ni;

    $nisql= mysqli_query($conn,"SELECT count(*) as ni FROM act WHERE activity='New Intake' AND new = '1'"); 
    $niintknum_row = mysqli_fetch_assoc($nisql);
    $niintknum = $niintknum_row['ni'];
    //echo $num;
    $niintk_num = $niintknum;

    if($niintk_num < 1) {
      $niintk_num = '0';

    echo $niintk_num;

    $brtvsql= mysqli_query($conn,"SELECT count(*) as rtrv FROM act WHERE activity='Box Retrieval' AND new = '1'"); 
    $brtv_row = mysqli_fetch_assoc($brtvsql);
    $brtvnum = $brtv_row['rtrv'];
    //echo $num;
    $brtv_num = $brtvnum;

    if($brtv_num < 1) {
      $brtv_num = '0';

    echo $brtv_num;


    $brtnsql= mysqli_query($conn,"SELECT count(*) as brtn FROM act WHERE activity='Box Return' AND new = '1'"); 
    $brtn_row = mysqli_fetch_assoc($brtnsql);
    $brtnnum = $brtn_row['brtn'];
    //echo $num;
    $brtn_num = $brtnnum;

    if($brtn_num < 1) {
      $brtn_num = '0';
    }
    echo $brtn_num;