谁可以帮我检查一下这段程序?
<?php include("navigation.php");?>
<html>
<head>
<title>图书馆管理系统</title>
<link href="CSS/style.css" rel="stylesheet">
</head>
<body>
<table width="776" border="0" align="center" cellpadding="0" cellspacing="0" class="tableBorder">
<tr>
<td valign="top" bgcolor="#FFFFFF"><table width="99%" height="510" border="0" align="center" cellpadding="0" cellspacing="0" bgcolor="#FFFFFF" class="tableBorder_gray">
<tr>
<td height="510" valign="top" style="padding:5px"><table width="98%" height="487" border="0" cellpadding="0" cellspacing="0">
<tr>
<td height="22" valign="top" class="word_orange">当前位置:系统设置 > 书架设置 >>></td>
</tr>
<tr>
<td align="center" valign="top">
<?php
include("conn/conn.php"); //连接数据源信息
$sql=mysql_query("select * from tb_bookcase order by id desc"); //查询图书书架信息表中的数据信息
$info=mysql_fetch_array($sql); //执行SQL语句
if($info==false){ //如果图书书架信息表中为空值,则弹出“暂无书架信息”
?>
<table width="100%" height="30" border="0" cellpadding="0" cellspacing="0">
<tr>
<td height="36" align="center">暂无书架信息!</td>
</tr>
</table>
<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td>
<a href="#" onClick="window.open('bookcase_add.php','','width=292,height=175')">添加书架信息</a> </td>
</tr>
</table>
<?
}else{ //否则输出书架信息
?>
<table width="91%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td width="84%"> </td>
<td width="16%" align="right">
<a href="#" onClick="window.open('bookcase_add.php','','width=292,height=175')">添加书架信息 </a> </td>
</tr>
</table>
<table width="91%" border="1" cellpadding="0" cellspacing="0" bordercolor="#FFFFFF" bordercolordark="#D2E3E6" bordercolorlight="#FFFFFF">
<tr align="center" bgcolor="#e3F4F7">
<td width="84%">书架名称</td>
<td width="16%">删除</td>
</tr>
<?php
do{ //应用do...while循环语句输出图书书架信息
?>
<tr>
<td style="padding:5px"><?php echo $info[name];?></td>
<td align="center"><a href="bookcase_del.php?id=<?php echo $info[id];?>">删除</a></td>
</tr>
<?
}while($info=mysql_fetch_array($sql)); //do...while循环语句结束
}
?>
</table></tr></td>
</table></tr></td>
</table>
<?php include(&q