PHP mysqli stmt unicode scrambled

Question

$HotelName = "Adams’ Inn";
$ID = 1;
$stmt = $sql->prepare("UPDATE coupons SET HotelName=? WHERE ID=?");
$stmt->bind_param("si",$HotelName,$ID);
$stmt->execute();

Output: Adams’ Inn

By the way, I have the following:

char set: utf8

collation: utf8_general_ci

Answer 1

checklist

1. $sql->set_charset('utf8') right after connect.
2. header('Content-Type: text/html; charset=utf-8'); before any output

There are 2 sides involved - server and client. Client means PHP script, not HTTP client. And server needs to know what encoding does client expect.
And you set only server side encoding, telling mysql in which encoding data have to be stored.
But there is also a client.

In fact, Mysql is great in recoding. As long as one encoding can be translated into other, Mysql can do it. For the different clients for example.
It is not too much demanded nowadays, but this feature exists. So, Mysql need to know which encoding is supported by client. For this very purpose set_charset() function exists.