小弟初学PHP，编一个BLOG
然后出现如下错误，甚是迷糊，可能是我PHPADMIN用的不太明白，请指教！
Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in D:\PHPnowV1.5\PHPnow\PHPnow-1.5.4\htdocs\sites\blogtastic\index.php on line 10
<?php
require("header.php");
$sql="select entries.*,categories.cat from entries,categories
where entries.cat_id=categories.id
ORDER BY dateposted DESC
LIMIT 1;";
$result = mysql_query($sql);
$row = mysql_fetch_assoc($result);
echo " <h2> <a href='viewentry.php?id=".$row['id']."'>".$row['subject']." </a> </h2> <br/>";
echo " <i>In <a href='viewcat.php?id=".$row['cat_id']."'>".$row['cat']." </a>-Posted on".date("D jS F Y g.iA",strtotime($row['dateposted']))." </i>";
echo " <p>";
echo nl2br($row['body']);
echo " </p>";
require("footer.php");
?>
以上是这个一面的源代码，帮我看看，谢谢啦~
用数据库运行一下你的sql语句，看看什么效果.
我也迷糊，你连连接数据库的代码都没有，不
