NULL
SELECT * FROM module_product WHERE site_id = ? AND is_draft = 0 AND parent_id = 0 AND is_gift = 0 ORDER BY id desc LIMIT 12
10%
SELECT * FROM module_product WHERE site_id = ? AND is_draft = 0 AND parent_id = 0 AND is_gift = 0 AND (price_discount > 0 OR discount_percent > 0) ORDER BY id desc LIMIT 6
