SELECT product_id FROM products_booked GROUP BY product_id HAVING count(*)  =  3
What is the id of the product that is booked for 3 times?
SELECT product_id FROM products_booked GROUP BY product_id HAVING count ( * ) = 3
select product_id from products_booked group by product_id having count ( * ) = value
What is the id of the product that is booked for 3 times ?