mysql_result() not able to find rsource

Question

I have the following code which echo the max id from my table challenge but its giving me this error :

Warning: mysql_result(): id not found in MySQL result index 6 in D:\xampp\htdocs\challenge.php on line 8

Here's my code:

<?php

    require('config.php');


        $result = mysql_query("SELECT max(id) FROM `challenge`");
        $id = mysql_result($result, 0, 'id');
        echo $id;
    ?>

My table challenge does have an id column then why PHP is not able to find. I do have a correct connection to my database.

Please, [don't use `mysql_*` functions](http://stackoverflow.com/questions/12859942/why-shouldnt-i-use-mysql-functions-in-php), They are no longer maintained and are [officially deprecated](https://wiki.php.net/rfc/mysql_deprecation). Learn about [prepared statements](http://en.wikipedia.org/wiki/Prepared_statement) instead, and use [PDO](http://us1.php.net/pdo) or [MySQLi](http://us1.php.net/mysqli). [This article](http://php.net/manual/en/mysqlinfo.api.choosing.php) will help you decide. — Jay Blanchard, Oct 14 '14 at 17:25

Mitya · Accepted Answer · 2014-10-14T17:37:47.577

5

Like it says, you're not returning a column called "id", you're returning one called "max(id)". If you want to refer to the column as "id" use an alias:

$result = mysql_query("SELECT max(id) AS id FROM `challenge`");

Note the AS id

(Sidenote: as Jay Blanchard says in his comment, mysql_* functions are deprecated over security concerns. Look into MySQLi and, as part of it, prepared statements, instead.)

edited Oct 14 '14 at 17:37

answered Oct 14 '14 at 17:07

Mitya

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score 0 · Answer 2 · answered Oct 14 '14 at 17:23

when using aggregate functions like Max, Min try to give an Alias then you can access it in result.

$result = mysql_query("SELECT max(id) as id FROM `challenge`");

but this function is slower than mysql_fetch_row(), mysql_fetch_array(), mysql_fetch_assoc() and mysql_fetch_object()

and secondly you should not use mysql_* functions instead use mysqli or PDO

mysql_result() not able to find rsource

2 Answers2