PHP mysql_real_escape_string returns empty string

Asked 2012-04-26T18:35:30.977

I'm trying to work a bit of security and sanitization into my databases application (for a class). to start off with, i'm trying to use mysql_real_escape_string, but whenever i use it, it always returns an empty string!

Here's the connection code:

include_once ("./connect.php");
$db_connection = new mysqli($SERVER, $USERNAME, $PASSWORD, $DATABASE);
if (mysqli_connect_errno()) {
    echo("Can't connect to MySQL Server. Error code: " . mysqli_connect_error());
    return null;
}
$field = mysql_real_escape_string($_GET['value']);
$upc = $_GET['upc'];
$type = $_GET['field_type'];
echo $field;
echo $upc;
echo $type;

When the php actually gets executed, the $upc and $type gets printed, but NOTHING for $field. Ive tried using an intermediate string, but i get the same result. I'm seriously at a loss as to what it is thats going wrong here.

Also, I've done a var_dump on $field, and it claims mysql_real_escape_string returns FALSE, which is supposed to happen when there isn't a connection(?), but there is one.

Edit Report

2 Answers

You are connecting using mysqli, not mysql, so you need mysqli_real_escape_string

Although you could easily use prepared statements in mysqli and then you wouldn't need either...

answered 2012-04-26T20:17:53.527

"This extension is deprecated as of PHP 5.5.0, and will be removed in the future. Instead, the MySQLi or PDO_MySQL extension should be used." from http://php.net/manual/en/function.mysql-real-escape-string.php

Simply adding "i" to the function name is not the solution. Notice the link identifier parameter is no longer optional http://www.php.net/manual/en/mysqli.real-escape-string.php

PS: As far as the downvotes, I stand by my answer. The function in the question is going to be removed from PHP, that's a big deal and I felt it needed to be pointed out since nobody else mentioned it. Do you disagree? The specifics of the original question are important but many people (including myself) came here looking for information on mysql_real_escape_string() and the first thing you should realize when looking for information about mysql_real_escape_string() is that it's deprecated. Sysadmins will have to upgrade PHP sooner or later and no doubt a ton of applications are still using this deprecated function.

answered 2013-07-08T20:20:34.750

PHP mysql_real_escape_string returns empty string

2 Answers

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