php条件下怎么实现点击左边记录名，具体内容在页面右边显示

<br><?php <br />	header("Content-Type:text/html;charset=utf-8");<br>	mysql_connect('localhost','colg_demo','colg__');<br>	mysql_select_db('colg_demo');<br>	function getdata($sql)<br>	{<br>		$result=mysql_query($sql);<br>		if($result)$count = mysql_num_rows($result);<br>		for($i=0;$i		{<br>			mysql_data_seek($result,$i);<br>			$data[$i] = mysql_fetch_assoc($result);<br>		}<br>		return $data;<br>	}<br><br>	$data = getdata("select * from demo");<br><br>?&gt;<br><style><br />	.left{float:left;width:100px;border:1px solid grey;height:300px;}<br />	.right{float:left;width:800px;border:1px solid grey;height:300px;margin-left:15px;}<br />	.left_button{margin:5px;border:1px solid #ccc;cursor:pointer;}<br />	td{margin:1px;border:1px solid #ccc;}<br /></style><br><br><script></script><br><script><br />	$(document).ready(function(){<br />		$(".left_button").click(function(){<br />			$(this).css("background","#EEE");<br />			$(this).siblings().css("background","white");<br />			var n = $(this).text();<br />			$.ajax({<br />				type:"get",<br />				url:"ajax.php",<br />				data:{<br />					n:n<br />				},<br />				success:function(msg){<br />						msg = eval("("+msg+")")<br />					$(".show_tr").html(msg);<br />				}<br />			});<br />		});<br /><br />	});<br />	<br /></script><br><br><div>
<br><?php  foreach($data as $each){?><br><div><?php  echo $each['col3'];?></div>
<br><?php  } ?><br>
</div><br><div>
<br><table>
<br><tr>
<br><td>id</td>
<div class="clear"></div>
</tr>
</table>
</div>