// Build this query:
// SELECT product_id, product_name, price
// FROM "products"
// WHERE (price < 100.00 OR price > 500.00)
// AND (product_name = 'Apple')

$minimumPrice = 100;
$maximumPrice = 500;
$prod = 'Apple';

$select = $db->select()
->from('products',
array('product_id', 'product_name', 'price'))
->where("price < $minimumPrice OR price > $maximumPrice")
->where('product_name = ?', $prod);