Determining the Number of Rows with the rowCount() Method

The rowCount() method returns the number of rows affected by the last SQL statement (e.g., how many rows were deleted, updated, or inserted). When used with SELECT statements, most drivers (including MySQL) return the number of rows found by the query. This is extremely useful when you want to verify if a search was successful before attempting to output any data.

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);
            $this->connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        } catch(PDOException $e) {
            die("Connection failed: " . $e->getMessage());
        }
    }

    public function countUsers() {
        $statement = $this->connection->prepare("SELECT * FROM users");
        $statement->execute();

        // The method returns the number of rows in the result
        $count = $statement->rowCount();
        
        return $count;
    }
}

// PART 3: Usage
$db = new Database();
$row_count = $db->countUsers();

echo "There are currently " . $row_count . " users in the table.";
?>

RESULT

The result will be displayed here...

Practical Application: This method is called on the prepared statement object (PDOStatement) after executing the execute() command. Check the process at home by following these steps:

Start the Apache and MySQL modules in the XAMPP control panel.
Ensure that the users table exists and contains test data within the pdo_db database.
The method returns an integer representing the number of processed rows.
Insert the example below into a PHP file and see how many users are currently in the database.