Is there a limit when using php mail function?

Question

I am using php and mysql.

I am going to send 10k++ (ten thousands plus) emails to update my subscribers, and this is the first time I am going to send them. I will use php mail function, basically here is what I will do:

First get the data from database:

Select name, email FROM data

After that, using while loop to send the data:

while($r = mysql_fetch_assoc($exe)){
    ...
    if($mail){
        echo "success<br>";
    } else {
        echo "failed<br>";
    }
}
echo "Sent all";

I include the if.. else statement, to ensure that each email is sent successfully. Is there anything I need to take care of? Will I have any problems when SENDING TO 10K++ users?

Is there a limit of numbers of emails that you are going to sent?

Answer 1

Please be aware of this note from the mail documentation:

Note: It is worth noting that the mail() function is not suitable for larger volumes of email in a loop. This function opens and closes an SMTP socket for each email, which is not very efficient.
For the sending of large amounts of email, see the » PEAR::Mail, and » PEAR::Mail_Queue packages.