PHP/ Mysql insert query working perfectly offline but not online

CREATE TABLE `s_news` (

id int(10) NOT NULL, news_id int(10) NOT NULL, username varchar(10) NOT NULL, newscat varchar(10) NOT NULL, img varchar(100) NOT NULL, newstitle varchar(225) NOT NULL, fullnews longtext NOT NULL, datetime timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP ) ALTER TABLE videos ADD PRIMARY KEY (id);

<?php
if(isset($_POST['post']))
{
$p_username = $suname;
$p_img = $_FILES['img']['name'];
$p_ttle = $_POST['posttitle'];
$p_cat = $_POST['cat'];
$p_title = htmlspecialchars($p_ttle);
$p_po = $_POST['fullpost'];
$p_p = htmlspecialchars($p_po);
$p_id = rand(0000,9999);
$query1 = mysql_query("INSERT INTO `s_news`(news_id,username,newscat,img,newstitle,fullnews)VALUES('$p_id','$p_username','$p_cat','$p_img','$p_title','$p_p')");
    if($query1){
        $newname_image = $p_id.".jpg";
        move_uploaded_file($_FILES['img']['tmp_name'],'../newspic/'.$newname_image);
    $OUTPUT_MESSAGE =  "Your news is been uploaded....Thanks";
    }   
    else
    {
    $OUTPUT_MESSAGE = "We have a problem uploading you post. See Admin";
    }
}
?>

I am new to php, I wrote this little code to upload some data. I've tried it in my xammp server, it works perfectly as I want it to. When I uploaded it to an online server, the SELECT query works fine but the INSERT query does not work. It does not insert at all.