php调用mysqli查询出错

语句直接在命令行运行就能查出接过来，在phpMyAdmin里面也能查到，但是写到程序里就出错，请大神帮忙看看。


代码是这个

 $sql =" select * from $table_list where $length_left qq $length_right $textif $t;";
 $mysqli = new mysqli("localhost","root","root",'qq_db');
$mysqli->set_charset("utf8");
if ($mysqli->connect_errno)
{
  die("Connect Error :".$mysqli->connect_error);  
}
$result = $mysqli->query($sql);
var_dump($result);
$mysqli->close();
sql语句实际输出的结果是
select * from qq_list where length( qq = 5)  and qq like '%1%' and wuzheng;

运行后就提示bool(false)

问题已解决，我把SQL语句调用的某个变量里的&nbsp去掉并且重新用双引号括起来就解决了。

应该要用引号把qq包起来把，你先试试

 $sql="select * from qq_list where length( 'qq'= 5)  and 'qq' like '%1%' and 'wuzheng';";

能不能运行