$email = $_POST['email']; if (!$db->requireField('users', 'email', $email)) { echo 'Error: Email address is required.'; }
$price = $_POST['price']; if (!$db->requireField('products', 'price', $price)) { echo 'Error: Price is required.'; }In this example, the function checks if the price field is present in the "products" table and returns an error message if it's missing. The requireField function is part of the Joomla Platform Database Library.