Question

Would this work? I know you can concatenate variables this way.

    while ($row = mysql_fetch_array($result)) {
          $recipients[] = $row['phone'] . $row['carrier'];
    }

    while ($row = mysql_fetch_array($result)) {
        $recipients[] .= $row['email'];
    }

Answer 1

It won’t work since you have already reached the end of the fetch (i.e. mysql_fetch_array will always return false in the second loop).

Moreover, it probably wouldn’t be a good idea if you wanted have some indicator of phone vs. email, but I guess you don’t:

$phones = array();
$emails = array();
while ($row = mysql_fetch_assoc($result)) {
   $phones[] = $row['phone'] . $row['carrier'];
   $emails[] = $row['email'];
}
$recipients = $phones + $emails;

Also, didn’t anyone tell you to use PDO or mysqli?