Customizing the Connection with the setAttribute() Method

The setAttribute() method is used to configure specific attributes on the database connection object. It allows us to define key settings such as the error reporting mode (ATTR_ERRMODE), result fetching behavior, or driver-specific options. Properly configuring these attributes immediately after establishing a connection ensures that your library behaves consistently and securely throughout the entire application lifecycle.

EXAMPLE

<?php
class Database {
    private $server = "localhost";
    private $username = "root";
    private $password = "";
    private $db_name = "pdo_db";
    public $connection;

    public function __construct() {
        try {
            // Added charset=utf8mb4 for character support
            $dsn = "mysql:host=" . $this->server . ";dbname=" . $this->db_name . ";charset=utf8mb4";
            $this->connection = new PDO($dsn, $this->username, $this->password);
            
            // 1. Set the error reporting mode
            $this->connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            
            // 2. Set all column names to be returned in lower case
            $this->connection->setAttribute(PDO::ATTR_CASE, PDO::CASE_LOWER);
            
            echo "Attributes have been successfully set.";
        } catch(PDOException $e) {
            die("Error: " . $e->getMessage());
        }
    }
}

// PART 3: Usage
$db = new Database();
?>

RESULT

The result will be displayed here...

Practical Application: Most commonly, we set the PDO::ATTR_ERRMODE attribute to PDO::ERRMODE_EXCEPTION, which enables PHP to throw an exception that can be caught whenever a database error occurs. Check the process at home by following these steps:

Start the Apache and MySQL modules in the XAMPP control panel.
The method is called directly on the connection object ($this->connection).
The first parameter is the attribute name, and the second is the desired value.
Insert the example below into a PHP file and see how we configure the database to force column names to lower case.