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HomeBackend DevelopmentPHP Tutorial PHP+MYSQL查询数据库罗致系统很卡

PHP+MYSQL查询数据库导致系统很卡!
PHP代码:

<br>
nbsp;html><!--STATUS OK-->    <br>
<meta><br>
<br>
<style><br />
table,td{border:1px solid #ccc;}<br />
td{padding:10px}<br />
<br />
</style><br>
<br>
<br>
<br>
<?php <br />
$dbh = @mysql_connect("localhost:3306","root","123456");<br>
 <br>
 /* 定义变量dbh , mysql_connect()函数的意思是连接mysql数据库, "@"的意思是屏蔽报错 */<br>
if(!$dbh){die("error");}<br>
/* die()函数的意思是将括号里的字串送到浏览器并中断php程式 (script)。括号里的参数为欲送出的字串。 */<br>
@mysql_select_db("data", $dbh);<br>
<br>
mysql_query("SET NAMES data");<br>
<br>
<br>
<br>
?><br>
<br>
<br><br><br><br>
<br>
<center>
<br>
<form>
<br>
<input><br>
<input><br>
<input><br>
<span><br>
<input></span>
</form>
<br>
<br>
</center><br>
<br>
<br>
$wd=$_POST["wd"];<br>
/* 选择mysql服务器里的一个数据库,这里选的数据库名为 ok */<br>
$q = "(select * from tabal where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal1 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal2 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal3 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal4 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal5 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal6 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal7 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal8 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal9 where user like '$wd%' or email LIKE '$wd%')<br>
union all<br>
(select * from tabal10 where email LIKE '$wd%')<br>
union all<br>
(select * from tabal11  where user like '$wd%' or email LIKE '$wd%') LIMIT 0,20";<br>
<br>
/* 定义变量q, "select * from abc"是一个sql语句,意思是读取表abc中的数据 */<br>
?><br>
<br><br>
<br>
<center>
<br>
<table>
<br>
<br>
<br>
$rs = mysql_query($q, $dbh);<br>
<br>
while($row = mysql_fetch_array($rs))<br>
<br>
echo "<tr>
<td>$row[user]</td> <td>$row[pass]</td> <td>$row[email]</td>
</tr> ";<br>
<br>
?><br>
<br>
</table>
<br>
<br>
</center><br>
 <br>
<br>
@mysql_close($dbh); <div class="clear">
                 
              
              
        
            </div>
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