the last page people visit before coming to the homepage? ➔ What are all the product pages people see after the homepage? ➔ How many people who visit the homepage go on to buy something? ➔ What if we limit that to buy within two days?
migrated to station 1 then station 3 before station 2? ➔ What drugs did people take in the last month before starting drug X? ➔ What was the last ad clicked before registering? ➔ What companies had their stock hit $100 per share then drop to $40?
their first registration afterward? 1. Filter landed for the first row per user 2. Left join with registered on user_id 3. Filter for timestamp.y > timestamp.x or NA 4. Filter for first row of timestamp.y
their last landing? 1. Filter landed for the last row per user 2. Filter registered for first row per user 3. Left join with registered on user_id 4. Filter for timestamp.y > timestamp.x or NA