Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result

PHP
1

Hi,

I have the following function to display posts on my site. It works fine on my localhost but when I uploaded the files to the server I got the following warning:

Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource

I can’t see what I am doing wrong because it works just fine on localhost. Any ideas?

function get_posts() {
	$query = mysql_query("SELECT
				`post_title`,
				`post_name`,
				`post_body`,
				`post_date`,
				`author_title`,
				`author_name`
				FROM `posts`
				WHERE `post_type` = 'post'
				LEFT JOIN `authors` ON `author_id` = `post_author`
				ORDER BY `post_id` DESC LIMIT 0,8");
	while ($row = mysql_fetch_assoc($query)) { $posts[] = $row;}
	return $posts;
}
2

Instead of jumping straight in the array you need some error catching to see whats going wrong, see the below example.

$query = mysql_query("QUERY GOES HERE") or die(mysql_error());
3

I tried that, it says there is some kind of syntax problem in the query that I can’t spot. I can’t spot because it works just fine on my localhost.

4

Could you please post the error that you receive?

5

the error is invalid syntax

you can’t put the WHERE clause there

it goes after the FROM clause, and the FROM clause includes all joins

pro tip: test your queries outside of php first

6

It is solved now, thanks for your help Chris and Rudy.

Following was the error I got:

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 'LEFT JOIN authors ON author_id = post_author ORDER BY post_id …

Thanks for the tip, I will definitely test my queries when I get such errors the next time. I now have the following and it works perfectly.

$query = mysql_query("SELECT 
                `post_title`, 
                `post_name`, 
                `post_body`, 
                `post_date`, 
                `author_title`, 
                `author_name`
                FROM `posts` 
                LEFT JOIN `authors` ON `author_id` = `post_author` 
                WHERE `post_type` = 'post'
                ORDER BY `post_id` DESC LIMIT 0,8");

I guess that my first query worked on the localhost and not on the server because they have different MySQL versions.

7

had to have been some other query

WHERE in front of LEFT JOIN has always been an error, in any mysql version, ever