Last answered:

01 Sept 2023

Posted on:

31 Aug 2023


I don't think 'min()' was used correctly in the video

Steps taken:

1. self join purchase table, name p1 and p2

2. group by p1.purchase_id

3. use min() to find the earliest purchase record for each purchase record

In the video, we group by p1.purchase_id, thus we should min(p2.purchase_date) instead of min(p1.purchase_date) in order to find the correct 'first_purchase_date'

1 answers ( 0 marked as helpful)
Posted on:

01 Sept 2023


Hi Wenhao, 

thanks for reaching out! I'll look at the code and get back to you as soon as I can. In the meantime, don't hesitate to reach out if you have any other comments or quesions about the course. 


365 Eli

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