<?php
$upto_date = '00-00-0000';

function is_customer($kb){
    global $debit_total, $upto_date;
    $id = $kb['id'];
    $customer = mysql_query("SELECT * FROM customer WHERE id = '$id' ");
    if(mysql_num_rows($customer) ==1 ){
        $cu = mysql_fetch_assoc($customer);
             $temp = $cu['grand_total'];
             $str = str_replace(array('.', ','), '' , $temp);
             $debit_total = $debit_total + $str;

            $temp_date = strtotime($cu['date']);
            $temp_upto = strtotime($upto_date);

             echo "DATE: " . $temp_date . "UPTO: " . $upto_date;
             if($temp_date <= $temp_upto){
                echo "<tr id='highlight'>";
            }else{
                echo "<tr>";
                }

?>

<?php
function is_reciept($kb){
    global $credit_total, $discount_total, $gr_total;
    $id = $kb['id'];
    $reciept = mysql_query("SELECT * FROM receipt WHERE id = '$id' ");
    if(mysql_num_rows($reciept) ==1 ){
        $re = mysql_fetch_assoc($reciept);

        global $upto_date;
        if(empty($re['upto'])){
            $upto_date = '00-00-0000';
        }else{
            $upto_date = strtotime($re['upto']);
            }

        $temp = $re['received_amount'];
        $str = str_replace(array('.', ','), '' , $temp);
        $credit_total = $credit_total + $str;

        $temp = $re['discount_amount'];
        $str = str_replace(array('.', ','), '' , $temp);
        $discount_total = $discount_total + $temp;

        $temp = $re['gr_amount'];
        $str = str_replace(array('.', ','), '' , $temp);
        $gr_total = $gr_total + $temp;
?>

//BOTH OF THESE FUNCTION ARE CALLED REPEATEDLY BECAUSE THEY ARE IN A LOOP.