Mysql error

<?php
$link = mysql_connect("host", "username", "pass");
mysql_select_db("db");
$result_set= mysql_query(SELECT id FROM `leden` WHERE `username` = '$naam');
$record= mysql_fetch_row($result_set);
foreach ($record as $value){
print "<em>$value </em>";  // print the row
}
mysql_close($link);
?>

<?php
$link = mysql_connect("host", "username", "pass");
mysql_select_db("db");
$result_set= mysql_query(SELECT id FROM `leden` WHERE `username` = '$naam');
$record= mysql_fetch_row($result_set);
foreach ($record as $value){
print "<em>$value </em>";  // print the row
}
mysql_close($link);
?>

$result_set= mysql_query("SELECT id FROM `leden` WHERE `username` = '".$naam."'");

$result_set= mysql_query("SELECT id FROM `leden` WHERE `username` = '".$naam."'");

print "<em>".$value."</em>";

print "<em>".$value."</em>";

foreach ($record as $value){
print "<em>$value </em>";  // print the row
}

foreach ($record as $value){
print "<em>$value </em>";  // print the row
}

<?php
while($rij = mysql_fetch_array($query))
{
print "<em>".$rij['value']."</em>";  
}
?>

<?php
while($rij = mysql_fetch_array($query))
{
print "<em>".$rij['value']."</em>";  
}
?>