语法my_real_escape_string无效的问题

$sql = "UPDATE 'biz_feedback'
    SET
        advice1 = '".mysql_real_escape_string($advice1)."',
        advice2 = '".mysql_real_escape_string($advice2)."'
    WHERE
        review_id = '".$_POST["review_id"]."'
        AND biz_id = '".$_POST["biz_id"]."'
        AND username = '".$_POST["post_review_username"]."'";
$result = mysql_query($sql) or die('Error, query'.$sql.'failed'.mysql_error());

带来此错误

Error, query
UPDATE 'biz_feedback'
SET
    advice1 = 'No issues but would be good to have more help to hand so person doesn''t have to go hunting for help',
    advice2 = ''
WHERE
    review_id = '1117'
    AND biz_id = '2371881'
    AND username = 'user'
failed

错误，查询更新"biz_feedback" 设置建议1 ="没有问题，但最好有更多的帮助，

这样人们就不必去寻求帮助"，建议2 ="没有更多的建议谢谢" 其中review_id='1117'，biz_id='2371881'和用户名=''失败你的SQL语法有错误;检查与您的服务器版本相对应的手册，了解在"biz_feedback"附近使用的正确语法 SET advice1 = '没有问题，但会很高兴得到更多的帮助'在1号线