SELECT distinct(p.product_id),p.* FROM categories c, products p, products_mappings pm WHERE c.category_id = pm.category_id and p.product_id = pm.product_id and parent_category_id in (2479,2509,2510,2511,2512,2513,2827,2515,2517,2518,2519,2520,2521) and p.online = 'Online' limit 400