xmlParseEntityRef: no name' warnings while loading xml - php

Question

Hello stackoverflow community,
this code display the url for my sitemap,
the connection work correctly and display the url list (not very well)
the error code i can see in the header
This page contains the following errors:
error on line 2 at column 18210: xmlParseEntityRef: no name
Below is a rendering of the page up to the first error.
<?php
header('Content-type: application/xml; charset=utf-8') ?>
<?php
echo '<?xml version="1.0" encoding="UTF-8"?>' ?>
<?php
define('DBHOST','localhost');
define('DBUSER','user');
define('DBNAME','database');
define('DBPWD','password');
$connect = new MySQLi(DBHOST,DBUSER,DBPWD,DBNAME)or die(mysqli_error());
echo '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">';
echo '<url>';
$query = $connect->query("select * from rss");
while($row=$query->fetch_array(MYSQL_ASSOC))
{
echo '<loc>'.$row['link'].'</loc>';
}
echo '</url>';
echo '</urlset>';
?>
the code above output this (does this look correct ?)
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
<url><loc>http://www.exemple.com/d/brown</loc>
<loc>http://www.exemple.com/d/blue</loc>
<loc>http://www.exemple.com/d/red/</loc>
<loc>http://www.exemple.com/d/yellow</loc>
//more lines
</url></urlset>
i would like to know what i did wrong on this code
thanks you very much
(French Pierre)

Answer 1

i fixed the problem ,the error came from one field in the rss table contain a bad character ..., but i have added missing xml parameters
lastmod, changefreq, priority
<?php
define('DBHOST','localhost');
define('DBUSER','user');
define('DBNAME','rss');
define('DBPWD','password');
$connect = new MySQLi(DBHOST,DBUSER,DBPWD,DBNAME)or die(mysqli_error());
header("Content-Type: text/xml;charset=iso-8859-1");
echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?>
<urlset xmlns=\"http://www.sitemaps.org/schemas/sitemap/0.9\">";
{
$query = $connect->query("select * from rss");
while($row=$query->fetch_array(MYSQL_ASSOC)) {
$url = $row["link"];
$time = $row["when"];
$lastmod = $time;
$datetime = new DateTime($lastmod);
$timeresult = $datetime->format('Y-m-d\TH:i:sP');
echo "<url>
<loc>$url</loc>
<lastmod>$timeresult</lastmod>
<changefreq>hourly</changefreq>
<priority>0.8</priority>
</url>
";}}
?>
</urlset>
like this the output does not give error anymore
it does pass google validation
thanks you