diff --git a/customer_bought_all_products b/customer_bought_all_products
new file mode 100644
index 0000000..fee03e0
--- /dev/null
+++ b/customer_bought_all_products
@@ -0,0 +1,6 @@
+SELECT  customer_id
+FROM customer c
+JOIN product p
+ON c.product_key = p.product_key
+GROUP BY 1
+HAVING COUNT(DISTINCT p.product_key) = (SELECT COUNT(*) FROM product);
\ No newline at end of file
diff --git a/product_sales_analysis_3 b/product_sales_analysis_3
new file mode 100644
index 0000000..4e3e4d5
--- /dev/null
+++ b/product_sales_analysis_3
@@ -0,0 +1,14 @@
+WITH cte AS(
+    SELECT  product_id,
+            MIN(year) AS min_year
+    FROM sales
+    GROUP BY 1
+)
+SELECT  s.product_id,
+        s.year AS first_year,
+        s.quantity,
+        s.price
+FROM sales s
+JOIN cte c
+ON c.product_id = s.product_id
+AND c.min_year = s.year;
\ No newline at end of file