MySQL simple Solution
Intuition\n Describe your first thoughts on how to solve this problem. \nIdentify all distinct products in the product catalog.\nDetermine which customers have 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\nIdentify all distinct products in the product catalog.\nDetermine which customers have purchased each of these distinct products.\nFilter out customers who have bought all the products.\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\nCount Total Distinct Products: First, we count the number of distinct products in the product catalog.\nGroup By Customer and Count Purchased Products: Then, for each customer, we count the number of distinct products they have purchased.\nFilter Customers: Finally, we filter out those customers whose count of distinct purchased products equals the total number of distinct products in the catalog.\n\n# Complexity\n- Time complexity: O(n + m)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: O(n + m)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\n# Write your MySQL query statement below\nSELECT c.customer_id\nFROM Customer c\nGROUP BY c.customer_id\nHAVING COUNT(DISTINCT c.product_key) = (SELECT COUNT(DISTINCT product_key) FROM Product);\n\n```
['MySQL']