How to draw a diagram correctly?

Question

Database design

Please help, I can't correctly draw a diagram based on the task for the database structure:

Development of a database for accounting for medicines

An information system is necessary to store information about medicines in a large pharmacy.
Each remedy is characterized by the type (vitamins, antibiotics, etc.), name, type of packaging (drops, drops, etc.), dosage, manufacturer.
The pharmacy receives goods from different suppliers, information about which also needs to be stored.
Each supplier supplies several types of medicines, at the same time, the same medicine can be supplied by different suppliers at different prices
. The pharmacy has several departments. Each medicine is sold only in one of them.
The pharmacy has regular customers. It can be a legal entity or an individual. I would like to know when and what purchases they made.
Customer information must also be stored in the information system.

Here's how I drew, but I'm not sure what is right, and I don't understand how to display the links

Answer 1

1 drugs - reference table
2 category - reference book
3 type of packaging - reference book
4 supplier - reference book
5 branches - base table
6 deliveries - base table with supplier delivery time and drug name
7 users - user attributes here
8 sales - actual sales fixation
9 discounts - discount information is stored here
This is all the basic structure, it may be worth adding sales analytics views. All base tables refer to dictionaries, some fields may need to be normalized and additional dictionaries created. It is also desirable to create an organization-contact hierarchy in order to apply corporate discounts. Well, to supplement the system with something like a chat to write Notes about customers and orders