问PHP如何通过while循环进行Whileloop

EN

<?php 
$sql3= "select * from pupil where parent=$parent_get";
$runsql3=mysqli_query($mycon,$sql3) or die ("no connection");
while($getpupils3=mysqli_fetch_array($runsql3)){
    $sid=$getpupils3["id"];
    $sname=$getpupils3["name"];
    $sclass=$getpupils3["class_id"];

    $sql = "Select * from class where id = $sclass";
    $runquery = $mycon->query($sql);
    if($runquery->num_rows > 0){
        $fetchdata=mysqli_fetch_array($runquery);
        $c_name=$fetchdata['name'];
        $c_title=$fetchdata['title'];
        $class_info=$c_name.' '.$c_title;
    }
    // output the pupil details before the fee while loop
    echo'<div class="col-lg-4">
        <div class="card m-b-30 card-body">
            <h4 class="card-title font-20 mt-0">'.$sname.'</h4>
            <p class="card-text">'.$class_info.'</p>';

    $sql4= "select * from fee where class=$sclass AND term=$term_get AND session=$session_get";
    $runsql4=mysqli_query($mycon,$sql4) or die ("no connection");
    $fee_total = 0;
    while($getpupils4=mysqli_fetch_array($runsql4)){    
        $fee_title=$getpupils4["fee_title"];
        $fee_amount=$getpupils4["fee_amount"];
        $fee_des=$getpupils4["fee_des"];
        // output the fee detail
        echo '<p class="card-text">'.$fee_title.': '.$fee_amount.'</p>';
        // increment the fee total
        $fee_total += $fee_amount;
    }
    // output the fee total
    echo '<p class="card-text">Total '.$fee_total.'</p>';
    // output the bottom of the box after the fee while loop
    echo '<a href="#" class="btn btn-primary waves-effect waves-light">Edit</a>
        </div>
    </div>';
}