diff --git a/CustomersWhoBoughtAllProducts.sql b/CustomersWhoBoughtAllProducts.sql
new file mode 100644
index 0000000..2f85519
--- /dev/null
+++ b/CustomersWhoBoughtAllProducts.sql
@@ -0,0 +1,8 @@
+'''
+https://leetcode.com/problems/customers-who-bought-all-products/description/
+'''
+
+SELECT customer_id
+FROM Customer
+GROUP BY customer_id
+HAVING COUNT(DISTINCT product_key) = (SELECT COUNT(*) FROM Product)
\ No newline at end of file
diff --git a/ProductSalesAnalysisIII.sql b/ProductSalesAnalysisIII.sql
new file mode 100644
index 0000000..63be6e5
--- /dev/null
+++ b/ProductSalesAnalysisIII.sql
@@ -0,0 +1,11 @@
+'''
+https://leetcode.com/problems/product-sales-analysis-iii/description/
+'''
+
+SELECT product_id, year AS first_year, quantity, price
+FROM Sales
+WHERE (product_id, year) IN (
+    SELECT product_id, MIN(year)
+    FROM Sales
+    GROUP BY product_id
+)
\ No newline at end of file