Setting up categories and subcategories in bubble database

Hi, I am struggling with setting up the database of online-store that sells electronic devices like smartphones, computers and etc. So the question is how should I build my database with categories and subcategories to store information about products? For example, I have category “Smartphones and Gadgets” and in this category I have subcategories “Smartphones, tablets and e-books, antivirus and softwares” . I need to set this database the way it will be easy for client (a man whom I am building this app for as an web-developer) to add products to database. Thanks in advance!

Have you considered making an admin-only page where the client can use a form to add new products to the database? That way the client can add products regardless of how the database schema is set up.

Yes, but I thought that it could be more professional to allow owner to load information that way.