提示SQLSTATE[HY093]: Invalid parameter number: parameter was not defined

代码如下

$sql = "select * from user where age>:age LIMIT :num";
$map = ['age'=>16 , 'nmu'=>2];
$res = Db::query($sql,$map);
var_dump($res);

错误提示：SQLSTATE[HY093]: Invalid parameter number: parameter was not defined

错误信息：[10501]SQLSTATE[HY093]: Invalid parameter number: parameter was not defined[D:\wwwroot\tp6.com\vendor\topthink\think-orm\src\db\PDOConnection.php:722]