1045. Customers Who Bought All Products

[QuXiangjie]

Question

My solution

WITH productnumber AS (
    SELECT COUNT(*) AS product_num
    FROM Product
)
SELECT customer_fullproduct.id as customer_id
FROM (
    SELECT c.customer_id AS id, COUNT(DISTINCT c.product_key) AS num
    FROM Customer c, productnumber
    GROUP BY c.customer_id
) AS customer_fullproduct, productnumber
WHERE customer_fullproduct.num = productnumber.product_num;

Remember that the where clause can be in the main SQL

WHERE customer_fullproduct.num = productnumber.product_num;

Better solution

# Write your MySQL query statement below
SELECT  customer_id 
FROM Customer 
GROUP BY customer_id
HAVING COUNT(distinct product_key) = (SELECT COUNT(product_key) FROM Product)

[ajimenez1101]

hi!