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You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-5,5' at line 7

<?php
class pagination
{
    public function __construct() {
    }
    public function calculate_pages($total_rows, $rows_per_page, $page_num) {
        $arr = array();
        // calculate last page
        $last_page = ceil($total_rows / $rows_per_page);
        // make sure we are within limits
        $page_num = (int) $page_num;
        if ($page_num < 1) {
           $page_num = 1;
        }
        elseif ($page_num > $last_page) {
           $page_num = $last_page;
        }
        $upto = ($page_num - 1) * $rows_per_page;
        $arr['limit'] = 'LIMIT '.$upto.',' .$rows_per_page;
        $arr['current'] = $page_num;
        if($page_num == 1) {
            $arr['previous'] = $page_num;
        } else {
            $arr['previous'] = $page_num - 1;
        }
        if($page_num == $last_page) {
            $arr['next'] = $last_page;
        } else {
            $arr['next'] = $page_num + 1;
        }
        $arr['last'] = $last_page;
        $arr['info'] = 'Page ('.$page_num.' of '.$last_page.')';
        $arr['pages'] = $this->get_surrounding_pages($page_num, $last_page, $arr['next']);
        return $arr;
    }
    function get_surrounding_pages($page_num, $last_page, $next) {
        $arr = array();
        if($page_num <= 4) {
            $show = 4;
            $pg_pos = 'l';
        } elseif($page_num > $last_page - 4) {
            $show = 4;
            $pg_pos = 'r';
        } else {
            $show = 3; // how many boxes
            $pg_pos = 'c';
        }
        //echo $pg_pos;
        // at first
        if ($pg_pos == 'l') {
            // case of 1 page only
            if($last_page == 1) return array(1);
            for ($i = 0; $i < $show + 1; $i++) {
                if ($i == $last_page) break;
                array_push($arr, $i + 1);
            }
            if($last_page > 6) array_push($arr, '...');
            return $arr;
        }
        // at last
        if ($pg_pos == 'r') {
            $start = $last_page - $show - 1;
            if ($start < 1) $start = 0;
            if($last_page > 6) array_push($arr, '...');
            for ($i = $start; $i < $last_page; $i++) {
                array_push($arr, $i + 1);
            }
            return $arr;
        }
        // at middle
        $start = $page_num - $show;
        if ($start < 1) $start = 0;
        array_push($arr, '...');
        for ($i = $start; $i < $page_num; $i++) {
            array_push($arr, $i + 1);
        }
        for ($i = ($page_num + 1); $i < ($page_num + $show); $i++) {
            if ($i == ($last_page + 1)) break;
            array_push($arr, $i);
        }
        array_push($arr, '...');
        return $arr;
    }
}
?>

$upto = ($page_num - 1) * $rows_per_page;

$upto = ($page_num - 1) * $rows_per_page;

$upto = ($page_num - 1) * $rows_per_page;
die($upto);

$upto = ($page_num - 1) * $rows_per_page;

$upto = ($page_num - 1) * $rows_per_page;
die($page_num);