PHP MySQLi mysqli_close() - Closing the Connection

mysqli_close()

The mysqli_close() function closes a previously opened database connection. This is a crucial step for releasing memory on the server.

EXAMPLE

<?php
$server = "localhost";
$username = "root";
$password = "";
$database = "mysqli_database";

// 1. Open the connection
$connection = mysqli_connect($server, $username, $password, $database);

// 2. Check the connection
if (!$connection) {
    die("Connection failed: " . mysqli_connect_error());
}

echo "Connection is open. Performing database work...<br>";

// 3. Close the connection
// NOTE: When you are finished reading or writing data, it is always wise 
// to close the connection manually. This immediately returns valuable 
// system resources to the server, which can be used by other visitors 
// of the website.
if (mysqli_close($connection)) {
    echo "The database connection was closed successfully.";
}
?>

RESULT

The result will be displayed here...

Practical use: Although PHP automatically closes connections at the end of script execution, it is good programming practice to close them manually as soon as the database is no longer needed.

Close the connection at the end of the file or immediately after the last query.

This prevents overloading the MySQL server when experiencing a high number of visitors.

Once the connection is closed, you can no longer execute queries until a new one is established.