So I am currently doing a semester project for school, and I decided to do a video game store and design something around that.

The thing is I'm confused how I would go about this.

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From the picture, you can see I rely on a primary key (inv_id) frequently with how I did it.

Is it wrong to have multiple tables with foreign keys referencing that primary key?

If so, what exactly could I do about it.

Thanks in advance.