更新mysqli多列错误PHP [重复]

Question

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• How can I prevent SQL injection in PHP? 28 answers

Hello i get this error when i try to update my database columns

ERROR 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

<?php
$id = $_POST['id'];
$title = urlencode($_POST['title']); 
$img = urlencode($_POST['img']);   
$url = urlencode($_POST['url']); 
$dec = urlencode($_POST['dec']);
mysqli_query($mysqli,"UPDATE posts SET title = $title, img = $img, url = $url, dec = $dec WHERE id = $id") or die(mysqli_error($mysqli));
?>

</div>

Answer 1

Please try below code. I hope it will works fine. If not let me know.

<?php
$id = $_POST['id'];
$title = urlencode($_POST['title']); 
$img = urlencode($_POST['img']);   
$url = urlencode($_POST['url']); 
$dec = urlencode($_POST['dec']);
mysqli_query($mysqli,'UPDATE posts SET title = "'.$title.'", img = "'.$img.'", url = "'.$url.'", dec = "'.$dec.'" WHERE id = **'.$id.'**') or die(mysqli_error($mysqli));
?>