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Author: ggeerraarrdd

README.md

@@ -151,6 +151,7 @@ To make the daily tasks of creating a new file and updating the index easier, th
 | 120   | [Classes More Than 5 Students](https://leetcode.com/problems/classes-more-than-5-students/description/)                                                       | [Solution](solutions/120_classes_more_than_5_students.md)                             | LeetCode    | Easy         |   |
 | 121   | [Find Followers Count](https://leetcode.com/problems/find-followers-count/description/)                                                                       | [Solution](solutions/121_find_followers_count.md)                                     | LeetCode    | Easy         |   |
 | 122   | [Biggest Single Number](https://leetcode.com/problems/biggest-single-number/description/)                                                                     | [Solution](solutions/122_biggest_single_number.md)                                    | LeetCode    | Easy         |   |
+| 123   | [Customers Who Bought All Products](https://leetcode.com/problems/customers-who-bought-all-products/description/)                                             | [Solution](solutions/123_customers_who_bought_all_products.md)                        | LeetCode    | Medium       |   |
 
 ## Author(s)
 

solutions/123_customers_who_bought_all_products.md

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+# SQL Everyday \#123
+
+## Customers Who Bought All Products
+
+Site: LeetCode\
+Difficulty per Site: Medium
+
+## Problem
+
+Write a solution to report the customer ids from the `Customer` table that bought all the products in the `Product` table.
+
+Return the result table in *any order*. [[Full Description](https://leetcode.com/problems/customers-who-bought-all-products/description/)]
+
+## Submitted Solution
+
+```sql
+-- Submitted Solution
+SELECT
+    customer_id
+FROM Customer
+GROUP BY customer_id
+HAVING COUNT(DISTINCT product_key) = (SELECT COUNT(product_key) FROM Product)
+;
+```
+
+## Site Solution
+
+```sql
+-- LeetCode Solution 
+-- Site solution essentially the same.
+```
+
+## Notes
+
+TODO
+
+Go to [Table of Contents](/README.md#contents)\
+Go to [Overview](/README.md)