will this INSERT profile work with my Mysql InnoDB oriented DB?

Question

I am wondering on the following subject (regarding INSERT on Mysql - InnoDB tables).

I have a system that does among other system 2 things

1. promote a newsletter to users
2. mass emails to a certain type of users

now, the users will grow to 4k, and supposedly to 40k

When I'm mass emailing, I'm doing an INSERT for each user id in a WHILE (which loops through all the users).

I have 2 questions :

1. Is this the best way to do it ?
2. When users reach 40K (40.000 users), will the mysql-server sustain this ?

thanks,

this is the piece of code i'm using

    $query_write_mass = "SELECT id FROM mya_users ORDER by artist_real_address ASC";
    $result_write_mass = $db->prepare($query_write_mass);
    $result_write_mass->execute();
    while ( list($receiver_id) = $result_write_mass->fetch(PDO::FETCH_BOTH) ) { 

       $stmt = $db->prepare
         ("INSERT INTO inbox(folder_id, sender_id, sender_type, receiver_id, 
           receiver_type, title, message_body, time, date, flag, spam) 
           VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

            $stmt->bindValue(1, 0, PDO::PARAM_INT);
            $stmt->bindValue(2, 0, PDO::PARAM_INT);
            $stmt->bindValue(3, 'x', PDO::PARAM_STR);
            $stmt->bindValue(4, $receiver_id, PDO::PARAM_INT);
            $stmt->bindValue(5, $receiver_type, PDO::PARAM_STR);
            $stmt->bindValue(6, $_POST['title'], PDO::PARAM_STR);
            $stmt->bindValue(7, $_POST['body'], PDO::PARAM_STR);
            $stmt->bindValue(8, date("G:i:s"), PDO::PARAM_STR);
            $stmt->bindValue(9, date("Y-m-d"), PDO::PARAM_STR);
            $stmt->bindValue(10, 'n', PDO::PARAM_STR);
            $stmt->bindValue(11, '', PDO::PARAM_STR);                                                                                                                                                                                                   

            $stmt->execute();   
     }

This is for the mass emailing for my internal email system.

UPDATE

You can find a good answer to this question in my other post (resolved) @

multiple INSERTS and keeping PDO prepared statement security

Answer 1

1) No. If you can, insert several rows at a time :

INSERT INTO t VALUES (1, 'something'), (2, 'something else')...

And if you insert a similar record for all users, an even better approach would be:

INSERT INTO t
SELECT 
    "something to insert for all users into t's column 1",
    "something to insert for all users into t's column 2",
    user.field1,
    user.field2
FROM user
-- WHERE some_condition_on_user_table

2) Yes, unless you proceed with while loops (but even then, it may just work too)

Answer 2

If you are asking if MySql can handle 40k inserts then, assuming space is available and the machine is reasonable, then this would be no problem. We have systems inserting hundreds of thousands of rows in a day.