Send an email to all users in a database

How does one go about sending emails to every user within a database without being flagged by any spam filters? I am assuming you would have to send the emails throughout the day in bursts over the course of a month or less. Of course, right off the bat, I can get all users email addresses with a simple query select 'email' from 'users' but implementing the proper way to do such a task is where I seem to be lost... In the past I have used services such as sendgrid, but what guidelines do these companies follow in order to stay clear of all spam filters?

3 Answers

Yes you can do it. follow the given code.

while($row = mysql_fetch_array($result))
{ $addresses[] = $row['email'];
}
$to = implode(", ", $addresses);
$subject = 'the subject';
$message = 'hello';
mail($to, "Your Subject", "A message set by you.", "If header information.");

First you have to gather all the email address as comma separated. after then just use a mail function to send mail to all user at the same time.

If you want to send mail separately then use:

while($row = mysql_fetch_array($result))
{ $to = $row['email']; $subject = 'the subject'; $message = 'hello'; mail($to, "Your Subject", "A message set by you.", "If header information.");
}

Updates:As mysql_* deprecated please use mysqli_* instead of all functions.

while($row = mysqli_fetch_array($result))
{ $addresses[] = $row['email'];
}
$to = implode(", ", $addresses);
$subject = 'the subject';
$message = 'hello';
mail($to, "Your Subject", "A message set by you.", "If header information.");

And

while($row = mysqli_fetch_array($result))
{ $to = $row['email']; $subject = 'the subject'; $message = 'hello'; mail($to, "Your Subject", "A message set by you.", "If header information.");
}

Please read the manual of mysqli_*.

Once you have your result set, you can loop through and call mail() on each 1. Let's hope that your server can handle this.

foreach($result as $user) { mail($user->email,"My subject",$msg);
}

I used PHPMailer to send emails. It's easy. Simply iterate all emails from DB and send using this library.