I don't understand the logic here

in SQL / Introduction to JOINs

It seams the one-to-one and one-to-many relationships don't follow the same logic in these two pictures. why?

1 answers ( 0 marked as helpful)

Tsvetelin Tsonkov

Instructor

Posted on:

21 Dec 2022

Hi Ramsey!
Thanks for reaching out.

A customer may purchase many products, but a particular product is linked to only one customer. Later, in the lecture the cardinanality constraints are added. So, please watch the whole lecture. Thank you.

Hope this helps.
Best,
Tsvetelin

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