I am getting the error when trying to execute my php script:
Fatal error: call to a member function fetch_array() on boolean in...
The code in question is here:
function backup()
{
    global $mysqli;
    $bup        = "SELECT p.product_id, p.ean, p.image, p.model,  p.status, p.price_sync, p.modified_by, p.date_modified, pd.name, pd.description, pd.language_id, pd.meta_description, pd.meta_keyword, pd.tag FROM oc_product p INNER JOIN oc_product_description pd ON p.product_id = pd.product_id";
    $backup     = $mysqli->query($bup);
    $megainsert = "REPLACE INTO oc_product_backup(product_id, ean, image, model,  status, price_sync, modified_by, date_modified, name, description, language_id, meta_description, meta_keyword, tag) VALUES ";
    while($row  = $backup->fetch_array(MYSQLI_ASSOC))
    {
        $product_id       = $mysqli->real_escape_string($row['product_id']);
        $ean              = $mysqli->real_escape_string($row['ean']);
        $image            = $mysqli->real_escape_string($row['image']);
        $model            = $mysqli->real_escape_string($row['model']);
        $name             = $mysqli->real_escape_string($row['name']);
        $description      = $mysqli->real_escape_string($row['description']);
        $meta_description = $mysqli->real_escape_string($row['meta_description']);
        $meta_keyword     = $mysqli->real_escape_string($row['meta_keyword']);
        $tag              = $mysqli->real_escape_string($row['tag']);
        $megainsert      .= "('".$product_id."', '".$ean."', '".$image."', '".$model."',  '".$row['status']."', '".$row['price_sync']."', '".$row['modified_by']."', '".$row['date_modified']."', '".$name."', '".$description."', '".$row['language_id']."', '".$meta_description."', '".$meta_keyword."', '".$tag."'),";
    }
    $backup->close();
    $megainsert = substr_replace($megainsert, "", -1);
    $dobackup   = $mysqli->query($megainsert);
    if(!$dobackup) return $mysqli->error;
    else return true;
}
the following line is where the problem is:
while($row  = $backup->fetch_array(MYSQLI_ASSOC))
The code right before the function above is as follows:
   function clearBackupPrices()
{
    global $mysqli;
    $clean   = "TRUNCATE TABLE oc_product_price_backup";
    $doclean = $mysqli->query($clean);
    if(!$doclean) return $mysqli->error;
    else return true;
}
 
     
    