I'm making an inventory management system using invoices.
- creating invoices (sale/transfer between warehouses or purchase)
- if purchasing new product => we will define new products in database
- we have currencies, units, account agent (supplier or customer) ...
- system will be able to add/modify delete all data(products,currencies,units
my db diagram is as follows
where should i put tva?
should i put tva final of all items in invoice table?
should i put the net amount in invoice table?
are the relationship true?