I would like to design a database of bookshop. I would like to control the stock of shop. orders detail,,, customer record,,, supplier.....Beside this,,,, I would like to manage the stock as when i entered the products from supplier then the stock should be updated (add item in existing item). if i sell the item to customer, then the stock should also be updated (minus the quantity from existing item.)..

Kindly help me and send the ERD with relation ship as soon as possible.

I shall be very thankful
Adnan Nasir Mughal