What is the internal structure of the customer-executor exchanges?

Question

Database

Good afternoon, dear toasters.
As a graduation project, I chose the topic "Development of a logistics portal". Mainly in order to understand for yourself and finally climb into the web.
Actually, the question is: where can I read about the organization of the structure of sites in the manner of "customer-executor" (like freelance exchanges)? Articles, books, forums - everything is welcome. It is clear that you can build a structure on your knees and it will work, but I want to see the modern architecture of a powerful web application.

Answer 1

these sites are no different from the rest
actually three tables
customers
executors
orders
The choice was also asked how to solve a quadratic equation

Answer 2

Puma is right, it's a bit more complex than a quadratic equation. To get started, you need only three voiced tables.
This is true for any application area: logistics, taxis, marketplaces , handyman services, freelance exchanges, etc. depending on the needs of the project.