Updating Error

[tomecerqueira]

Hi there!
I cannot update my table when i change information. The row highlighted red and not update the information

update.php

<?php

/*
 * 
 * This file is part of EditableGrid.
 * http://editablegrid.net
 *
 * Copyright (c) 2011 Webismymind SPRL
 * Dual licensed under the MIT or GPL Version 2 licenses.
 * http://editablegrid.net/license
 */

require_once('config.php');         

// Database connection                                   
$mysqli = mysqli_init();
$mysqli->options(MYSQLI_OPT_CONNECT_TIMEOUT, 5);
$mysqli->real_connect($config['db_host'],$config['db_user'],$config['db_password'],$config['db_name']); 

// Get all parameters provided by the javascript
$colname = $mysqli->real_escape_string(strip_tags($_POST['colname']));
$id = $mysqli->real_escape_string(strip_tags($_POST['id']));
$coltype = $mysqli->real_escape_string(strip_tags($_POST['coltype']));
$value = $mysqli->real_escape_string(strip_tags($_POST['newvalue']));
$tablename = $mysqli->real_escape_string(strip_tags($_POST['tablename']));



// This very generic. So this script can be used to update several tables.
$return=false;
if ( $stmt = $mysqli->prepare("UPDATE $tablename SET $colname = $value WHERE idoferta = $id")) {
    $return = $stmt->execute();
    $stmt->close();

}             
$mysqli->close();        

echo $return ? "ok" : "error";

If you need anything else, let me know.
Thank You for the help ;)

[tomecerqueira]

My bad...

I deleted some important parts, like this:

Previous

if ( $stmt = $mysqli->prepare("UPDATE $tablename SET $colname = $value WHERE idoferta = $id")) {
    $return = $stmt->execute();
    $stmt->close();

}

After

if ( $stmt = $mysqli->prepare("UPDATE ".$tablename." SET ".$colname." = ? WHERE idoferta = ?")) {
    $stmt->bind_param("si",$value, $id);
    $return = $stmt->execute();
    $stmt->close();

}

I deleted the parameters and change the '?' in the query. Sorry