php网页中提示提供的参数不是有效 MySQL 结果中的资源

Question

<?php

$k=$_POST['cx'];
//$link=mysql_connect("localhost","root","12345678") or die("数据库服务器连接错误".mysql_error());
//mysql_select_db("gdaib",$link) or die("数据库访问错误".mysql_error()); //选择数据库
//mysql_query("set names utf-8");
//mysql_query("SET CHARACTER SET UTF8"); 
//mysql_query("SET CHARACTER_SET_RESULTS=UTF8"); 
$sql=mysql_query("select * from news where 'bt' like '%'".$k."'%'");
$row=mysql_fetch_row($sql);                    
    do{
        ?>
  <tr>
    <td> <a href="wo.php?id=<?php echo $row[0];?>"><?php echo $row[1]?></a></td>
    <td><?php echo $row[5];?></td>
  </tr>
<?php
 }while($row=mysql_fetch_row($sql)); 
 
?>