In what normal forms is a simple DB, why, and how can it be maximally normalized?

[June7]

I am not formally trained in RDBMS concepts. I don't really give much thought to the 'forms'. My philosophy is it's a balancing act between normalization and ease of data entry/edit and I follow the guideline of "Normalize until it hurts, denormalize until it works."

Having that said, I will agree that in most cases, 3NF is far enough.

An out_of_stock field may be inappropriate as stock balances would normally be calculated from transaction records.

[Math-IT-Lang]

I am not formally trained in RDBMS concepts. I don't really give much thought to the 'forms'. My philosophy is it's a balancing act between normalization and ease of data entry/edit and I follow the guideline of "Normalize until it hurts, denormalize until it works."

Having that said, I will agree that in most cases, 3NF is far enough.

An out_of_stock field may be inappropriate as stock balances would normally be calculated from transaction records.

Thank you for your kind reply.
I'm not formally trained in concepts like normalization in RDBMS either, but I'm just scratching my head with this sort of thing. But it seems that knowing these notions makes the database more functional, leading to elimination of update anomalies, etc. of data and to several possible queries.

In my previous reply I meant to say that I consider the above database in 3NF (and possibly in 4NF etc.)

Also I consider the out_of_stock field appropriate because depending on its value (Yes/No) we can create other queries such as: What is the total amount obtained from the sale of out-of-stock books grouped by bookstores, sorted by bookstores?