我想从一个数据表中按pingfen字段选出前十个。这样写怎么不对呢？查询数据那里有错误
<?php
$dbhost="localhost";
$dbname="myfan4"; //数据库名称
$dbuser="myfan4"; //数据库用户
$dbpassword="000000"; //数据库密码
$dbtable="sengo_pfdata"; //数据表名
$connect=mysql_connect($localhost,$dbuser,$dbpassword) or die("Unable to connect to MySQL");
mysql_select_db("$dbname",$connect) or die("Unable to Select default database");
?>
<?
$song_query="select pingfen,id,txt_category_id,txt_class_id,txtshowname from $dbtable order by $pingfen desc limit 0,10";
$song_result=mysql_query($song_query);
while($song_row=mysql_fetch_array($song_result)) {
$pingfen=$song_row[pingfen];
$id=$song_row[id];
$txt_category_id=$song_row[txt_category_id];
$txt_class_id=$song_row[txt_class_id];
$txtshowname=$song_row[txtshowname];
echo "$pingfen\t$id\t$txt_category_id\t$txt_class_id\t$txtshowname";
}
mysql_close($connect);
//mysql_free_result($song_result);
?>