MySQL PHP adding 3306 without my input - php

Question

I have a back end cron script that checks MySQl regurlarly for an if-then condition and then runs a Curl action. Anyway, the script has been running fine for over a year now when suddenly a problem occured and it does not make sense to me
here is the truncated code for the script
<?php
//assign values to variables
$servername = "localhost:3306";
$username = "username";
$password = "password";
$database = "database";
$con = mysqli_connect($servername, $username, $password, $database);
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$results = "SELECT NewUserID FROM queue ORDER BY ID";
$queryresults = $con->query($results);
if($con->error) {
printf("Errormessage: %s\n", $con->error);
die();
}
I would see this error:
Warning: mysqli_connect(): (HY000/2002): Failed to parse address "localhost:3306:3306" in /home/foo/bar/BackEnd.php on line 11
Failed to connect to MySQL: Failed to parse address "localhost:3306:3306"
Fatal error: Uncaught Error: Call to a member function query() on boolean in /home/foo/bar/BackEnd.php:19
Stack trace:
#0 {main}
thrown in /home/foo/bar/BackEnd.php on line 19
The solution was simple, I change "localhost:3306" to "localhost" and everything worked again, since it seemed that ":3306" was being added to what was already there. This solution seems like a problem waiting to happen but im not sure what went wrong in the first place. Any ideas?

Answer 1

You can't specify the port in the host parameter.
Here is the full function definition:
mysqli_connect($host, $username, $password, $dbname, $port, $socket);
You should just add the port at the end of your call. Like this:
$con = mysqli_connect($servername, $username, $password, $database, 3306);