I don't understand the logic here.
in SQL / Introduction to JOINs
It seems the one-to-one and one-to-many relationships don't follow the same logic in these two pictures, why?
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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.
I did understand the top picture relationship. I have a hard time understanding the bottom picture relationships. Looking at employees and salaries table it looks like their relationship shown as one to many. An employee can have multiple salaries, but a particular salary is linked to only one employee! That's what it says. Why?
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