mysqli_real_escape_string（）在数据库中不起作用

Question

我正在使用mysqli_real_escape_string()函数来防止SQl注入。我的代码

<?php

// open a connection
$dhost = 'localhost';
$duser = 'user';
$dpw = 'pass';
$dname = 'db_name';
$connection = mysqli_connect($dhost, $duser, $dpw, $dname);

// test the connection
if(mysqli_connect_errno()){
    die('Something went wrong with the database<br><br> '
    . mysqli_connect_error() . ':' 
    . mysqli_connect_errno());
}

$query = "Isn't it nice that we don't have to escape ' characters all by ourselves?";

echo $query.'<br>';

$escaped = mysqli_real_escape_string($connection , $query);

echo $escaped.'<br>';

mysqli_query($connection,"INSERT into emp (name) VALUES ('$escaped')");
   mysqli_close($connection);

?>

当我打印$ escaped变量时，它给出如下输出：

我们不必自己逃脱\'字符不是很好吗？

但是当我看到数据库字段时，我发现了这一点：

我们不必自己逃脱'个字符，这很好吗？