PHP MySQLi mysqli_change_user() - Advanced Database Switching

mysqli_change_user()

The mysqli_change_user() function changes the user of the specified database connection and sets a new active database, completely resetting the session in the process.

EXAMPLE

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

// Establish the first connection to database A
$connection = mysqli_connect($server, $username, $password, $database_A);

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

// UPGRADE: Changing the user/database with success verification
// NOTE: We are not opening a new connection with mysqli_connect here.
// The same connection simply switches to another database (database_B).
if (mysqli_change_user($connection, $username, $password, $database_B)) {
    
    // Check which database is currently active
    $result = mysqli_query($connection, "SELECT DATABASE()");
    $row = mysqli_fetch_row($result);
    
    echo "The database has been changed successfully. The current database is: " . $row[0];
} else {
    echo "Error: Database switch failed.";
}

mysqli_close($connection);
?>

RESULT

The result will be displayed here...

Practical use: This function is used when we want to completely reset the session and change the database within the same script. The advantage is that the function releases all locked tables and closes temporary tables, ensuring a clean working environment. Test it at home like this:

Create two databases with different names in your MySQL server (phpMyAdmin).

Use the function to switch to the second database without closing and reopening the connection.

Check the output – if you see the name of the new database, the switch was successful and the session has been refreshed.