Multiple purchase prices and sale prices for same book title.

[pepenino]

I'm using Access to create a database for my used book business. I buy books that have the same author/title at multiple purchase prices and sell at multiple sale prices. It may be a soft cover vs. hard cover price difference, or the price might just be a different based on the quality of appearance of two books purchased with the same author/title.



I need to be able to get the purchase price into the same table as the book titles but don't want to create multiple IDs for the same book title. Any ideas?

[orange]

Yes. Think about what you are asking.
You have multiple copies of the same Title/Author.
Some copies are soft cover, some hard cover
Copies may differ in quality of appearance, (rips, tears, dog ears....)

So you want to have 1 price for a Title??? I don't think so---unless

You have a price for a given title, and you double or half that price for hard/soft cover.
You reduce price by a percentage for each base don some categorization.
-immaculate never been opened
-above average --no rips/tears, no writing or highlighting
-average --a few creases, very minor rips/tears/highlighting
-below average --"dog-earred", rips/highlighting (heavily used)

My suggestion --uniquely identify each copy; add a condition category; price each copy.

But you know your business better than we do. Tell us more details of what your business and rules are.
Look to someone in the business of book selling/reselling eg Amazon.com see what they do; adapt to fit your needs.

Your database has to meet and support your business.

Good luck.

[pepenino]

Hi Orange,

Thanks for the reply and the advice. I was hoping not to have to add more distinguishing fields to the table/form in order to keep a single ID for the same author/title, but I asked the question because I was afraid that there was no way around it. Unfortunately, you're confirming that suspicion.

[orange]

I'm just trying to think through the issue.
You have things for sale. Even if they have the same Title -they differ from each other (or could do) because of cover type, condition....
So conceptually these are different things, and so would be handled on a thing basis, not simply by Title.

You ask yourself, when looking at entities when building a data model, is this the same as that. What makes them the same?
If they aren't the same, then what is it that makes them different? Once you're convince that they are different, identify the attributes and values that make them different, and treat them as separate things.

Good luck with your project.

[pepenino]

Orange,

Thanks again for your thoughts. I'm working on a solution that treats each "thing" as a different entity.