Simple Solution using ARRAY_AGG()
\n# Approach\nNot used count of the products, Instead Ensured exact items are present or not. Using ARRAY_AGG() function aggreagted all the product_id then comp
\n# Approach\nNot used count of the products, Instead Ensured exact items are present or not. Using ARRAY_AGG() function aggreagted all the product_id then compared with the Product table.\n\nIf we tried to match with Counts, may be fail in some other test cases, here this won\'t fail at any cost\n\n\n# Code\n```postgresql []\n-- Write your PostgreSQL query statement below\nSELECT c.customer_id FROM Customer c LEFT JOIN Product p ON c.product_key = p.product_key \nGROUP BY c.customer_id \nHAVING ARRAY(SELECT product_key FROM Product ORDER BY product_key)  <@ ARRAY_AGG(c.product_key)ORDER BY 1\n```
['PostgreSQL']