Close mysqli connection in another file

Question

Let's assume I have 2 php files
In the first one I have the connection to the database. Since I need it in another php files, I assigned it to a global variable like this.

setconnection.php

<?php
$servername = 'localhost';
$username = 'root';
$password = '';
$dbname = 'database';

// Create connection
$GLOBALS['connect'] = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($GLOBALS['connect']->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}
$db_selected=mysqli_select_db($GLOBALS['connect'],'database');
mysqli_set_charset($GLOBALS['connect'],'utf8');
?>

And then I have another php file in which I use the connection from the above php file.
It is correct to close the connection like this?

index.php

include_once "setconnection.php";
$GLOBALS['connect']->close();

score 0 · Answer 1 · answered Feb 17 '17 at 14:57

0

Good Question! I never see it anywhere in the examples. Closing connection will only save you memory resources. Php is supposed to close non-persistent connection after script execution anyway. However, it may not always be the case. I have had server CPU overloads when legacy code persistently omitted closing connections. As of now, we keep one connection for several functions, which in essence is the same thing you are doing. Works well for us.

Reference: http://php.net/manual/en/mysqli.close.php

answered Feb 17 '17 at 14:57

Ochkarik

31
5

My problem is that I have a function defined in setconnection.php, and if I close the connection in the end of that file, I can't call the function in other php files... – Daniel Feb 17 '17 at 15:01
1

@Daniel don't close it then? – Your Common Sense Feb 17 '17 at 15:40
@YourCommonSense I know that php closes connections in the end. But i found some advices around here where it says that if you don't close your connection by yourself it can lead to CPU overusage. – Daniel Feb 17 '17 at 16:00
1

@Daniel don't listen to them – Your Common Sense Feb 17 '17 at 16:03

score -1 · Answer 2 · answered Feb 17 '17 at 15:04

-1

In my opinion, this is legit. Do not forget to check if the connection is really open or not already closed before closing it.

answered Feb 17 '17 at 15:04

qdruault

63
9

score -1 · Answer 3 · edited May 23 '17 at 11:53

-1

This is totally legit, as said by Pekka on Are PHP include paths relative to the file or the calling code?,

... remember that include() just inserts code into the currently running script

So, let's say you have a file called example.php:

function example() {
    echo 'Hello, world!';
}

And you include it in index.php:

include 'example.php';
example();

This is the same as having everything in one file:

function example() {
    echo 'Hello, world!';
}

example();

So there's really not any error in closing the connection in another file which is not the one where you opened the connection.

edited May 23 '17 at 11:53

Community

1
1

answered Feb 17 '17 at 15:27

Condorcho

503
4
12

I hope nobody would follow your idea – Your Common Sense Feb 17 '17 at 15:37
I'm not very experienced in PHP, but, why not? – Condorcho Feb 17 '17 at 15:43
because a connection should be opened once. – Your Common Sense Feb 17 '17 at 15:45

Close mysqli connection in another file

3 Answers3