PHP新手有关问题：首次进页面select全部数据，点击条件后按条件select数据库数据

<br /><?php<br />$where="where 1=1";<br />if(isset($_POST['seach']))<br />{<br />	if(!empty($_POST['name'])) $where.=" and name='$_POST[name]'";<br />	if(!empty($_POST['age'])) $where.=" and age='$_POST[age]'";<br />}<br />$sql="select * from table {$where}";<br />echo $sql;<br />?><br /><form action="" method="post"><br /><input type="text" name="name" value="" /><br /><input type="text" name="age" value="" /><br /><input type="submit" name="seach" value="seach" /><br /></form><br />