PHP PDO Connect - Establishing a Database Connection

Database Connection (PDO CONNECT)

The PDO (PHP Data Objects) library uses an object-oriented approach to connect to databases. The main advantage of PDO is that it supports various types of databases (not just MySQL) and uses a consistent coding style for all of them.

EXAMPLE

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

try {
    // DSN (Data Source Name) specifies the driver type (mysql), host, and database name.
    // NOTE: Always add charset=utf8mb4 directly to the DSN string, as this ensures proper handling 
    // of special characters (like non-English letters) as soon as the connection is established.
    $dsn = "mysql:host=$server;dbname=$database;charset=utf8mb4";
    
    // Creating a new PDO object automatically opens the connection to the database
    $connection = new PDO($dsn, $username, $password);
    
    // Set error reporting mode to Exceptions
    // This is crucial, as any failed SQL statement will immediately trigger an exception, 
    // which we catch in the catch block below, instead of the script silently continuing.
    $connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    
    echo "PDO connection was successful!";
} catch (PDOException $e) {
    // If the connection fails, the code in the try block is interrupted and this security block is executed
    echo "Connection failed: " . $e->getMessage();
}

// Closing a PDO connection is done by simply assigning null to the object
$connection = null;
?>

RESULT

The result will be displayed here...

To establish a connection, we need three key elements: a DSN (Data Source Name), a username, and a password. With PDO, it is a best practice to wrap the connection in a try...catch block, which captures potential errors (exceptions) if the connection fails.

The DSN string defines the driver type (mysql), host, and database name (dbname).

The try block contains the code we want to execute.

The catch block catches the error (PDOException) without revealing sensitive information to the user.