Show the product ids and the number of unique orders containing each product.
CREATE TABLE Order_items (product_id VARCHAR, order_id VARCHAR)
SELECT product_id, COUNT(DISTINCT order_id) FROM Order_items GROUP BY product_id
### Context: CREATE TABLE Order_items (product_id VARCHAR, order_id VARCHAR) ### Question: Show the product ids and the number of unique orders containing each product. ### Answer: SELECT product_id, COUNT(DISTINCT order_id) FROM Order_items GROUP BY product_id