Create ad-free-sessions.sql

Author: kamyu104

MySQL/ad-free-sessions.sql

@@ -0,0 +1,9 @@
+# Time:  O(n)
+# Space: O(n)
+
+SELECT p.session_id
+FROM   playback p
+       LEFT JOIN ads a
+              ON p.customer_id = a.customer_id
+                 AND a.timestamp BETWEEN p.start_time AND p.end_time
+WHERE  a.customer_id IS NULL;