How do I diagnose a MySQL query failure in a PHP page? - php

Question

I am trying to create sitemap.xml file and get all brands from my database. I have following code:
<?php
header("Content-type: text/xml");
echo'<?xml version=\'1.0\' encoding=\'UTF-8\'?>';
echo'<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">';
include 'includes/modules/connections/db.php'; //database connection
$brands = mysql_query("SELECT * FROM brands WHERE brand_status = 1"); //Select all brands
$row_brands = mysql_fetch_assoc($brands);
do { ?>
<url>
<?php
//Check when brand pages was last time updated
$brand_update = mysql_query("SELECT * FROM user_history WHERE brand_id = ".$row_brands['brand_id']." ORDER BY uh_date DESC");
$row_brand_update = mysql_fetch_assoc($brand_update)
?>
<loc>http://www.example.com/brand/<? echo $row_brands['brand_url']; ?>/</loc>
<lastmod><?php echo $row_brand_update['uh_date']; ?></lastmod>
<changefreq>daily</changefreq>
<priority>0.7</priority>
</url>
<?php } while ($row_brands = mysql_fetch_assoc($brands)); ?>
</urlset>
however I get below errors. I tried many changes but always come up with different error. Anyone sees a problem in above code that cause below error?
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
<br/>
<b>Warning</b>
: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in
<b>
/hermes/bosoraweb060/b2763/ipg.example/sitemap-brands.php
</b>
on line
<b>8</b>
<br/>
<url>
<br/>
<b>Warning</b>
: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in
<b>
/hermes/bosoraweb060/b2763/ipg.example/sitemap-brands.php
</b>
on line
<b>15</b>
<br/>
<loc>http://www.example.com/brand//</loc>
<lastmod/>
<changefreq>daily</changefreq>
<priority>0.7</priority>
</url>
<br/>
<b>Warning</b>
: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in
<b>
/hermes/bosoraweb060/b2763/ipg.example/sitemap-brands.php
</b>
on line
<b>22</b>
<br/>
</urlset>
Thanks a lot got help!

Answer 1

SWITCH TO SOMETHING BESIDES mysql_ ! Keep using mysql and the intertoobz wil pwn ur w3bs1te, srsly. That being said, I will answer your question in the context you asked it.
Your first error message, when you untangle the HTML from it, says this:
Warning : mysql_fetch_assoc(): supplied argument is not a valid MySQL
result resource in
/hermes/bosoraweb060/b2763/ipg.example/sitemap-brands.php on line 8
You can look at line 8 of your code and see that there's only one argument passed to that function. That argument was produced by this line in your code:
$brands = mysql_query("SELECT * FROM brands WHERE brand_status = 1");
So, this thing $brands that you're trying to get back from mysql_query is no good (it's not a valid MySQL result resource).
What could be wrong? Your SELECT statement has failed.
That could be because your database doesn't contain a brands table, or because it does contain a brands table but that table has no brand_status column.
It also could be because you need to call mysql_select_db("database") before you run a query. Look at this: http://www.php.net/manual/en/function.mysql-select-db.php
You should probably adjust your code to include the following lines right after your call to mysql_query(). This will cause your program to show you the error messages from MySQL itself, not just the PHP, so you can figure out what's going wrong in your SELECT.
if (0 != mysql_errno()) {
echo mysql_errno() . ": " . mysql_error(). "<br/>\n";
exit ("MySQLfailure.<br/>\n");
}
You can put this right after every query, and leave it in your production code.