Validate multiple PHP generated checkboxes into MySQL

It looks like this:

and this is what I have tried so far:

<?php
require ('includes/config.php');

// if not logged in redirect to login

if ($user->is_logged_in())
    {
    }
  else
    {
    header('Location: login.php');
    }
$title = "Approve leaves";

if($_SESSION["admin"] == 0){
     $page = date('F');
    $page = lcfirst($page);
    header("Location: $page.php");
}

require ('layout/header.php');

?>

<?php
if(isset($_POST['submit'])){
$count = count($_POST);
$count = $count -1;
for($l = 0; $l < $count; $l++){
echo $_POST[$l];

$result = mysql_query("select name, surname from employee where employee_ID =  $id");
                    while ($row = mysql_fetch_assoc($result)) {
                    $employee[] = $row;
                    }

}
}



$i = 0;
$query = "SELECT * from absences WHERE approved = 0";

$result = mysql_query("$query");
                    while ($row = mysql_fetch_assoc($result)) {
                    $unapproved[] = $row;
                    $i++;
                    }


?>

<div class="container">
        <div class="row">
            <div class="col-xs-12 col-sm-8 col-md-6 col-sm-offset-2 col-md-offset-3">
              <form role="form" method="post" action="" id="form">
                <h2><?php echo $title ?></h2>
                    <?php 
                        $page = date('F');
                        $page = lcfirst($page);
                        echo "<p><a href='$page.php'>Back</a></p>";
                    ?>
                    <hr>
                <?php



                if($i == 0){
                echo "<h3>No unapproved leaves.</h3>";
                }else{
                echo '<table class="table table-striped table-hover">';
                echo '<thead>';
                    echo '<th>';
                    echo 'Start';
                    echo '</th>';
                    echo '<th>';
                    echo 'End';
                    echo '</th>';
                    echo '<th>';
                    echo 'Employee';
                    echo '</th>';
                    echo '<th>';
                    echo 'Approve';
                    echo '</th>';
                echo '</thead>';
                echo '<tbody>';
                for($j =0; $j < $i; $j++){


                echo '<tr>';
                    echo '<td>';
                    echo $unapproved[$j]['start'];
                    echo '</td>';
                    echo '<td>';
                    echo $unapproved[$j]['end'];
                    echo '</td>';
                    echo '<td>';
                    $id = $unapproved[$j]['employee_FK'];
                    $result = mysql_query("select name, surname from employee where employee_ID =  $id");
                    while ($row = mysql_fetch_assoc($result)) {
                    $employee[] = $row;
                    }
                    echo $employee[0]['name'], " ", $employee[0]['surname'];
                    echo '</td>';

                    echo '<td>';
                    echo "<input type='checkbox' name='$j' value='1' id='$j'>";
                    echo '</td>';
                echo '</tr>';
                }
                echo '</tbody>';
                echo '</table>';
                }

                ?>
                <input type="submit" name="submit" value="Submit" class="btn" >
            </div>

        </div>



    </form>
</div>

<?php
require ('layout/footer.php');
?>

The problem is that I only have the order of the checkboxes and if they are approved or not. I need to get the absence_ID from the MySQL table. In order to do that I need the employee_ID, so probably something like this:

select absences_ID from absences wehere employee_ID = $employee_Fk

But how do I get the employee_FK with the results from the checkboxes? I dont really wanna send the employee_FK in the name of the form.