Non-Multi Tenant App (Common Table/App) for "Customer"

Hi, As part of our project, we need to build an App “Customer” (similar to User) regardless of multi-tenant sites.
The customer can access all the sites he has interacted with with a single credential. (We don’t need to keep the customer app (or DB table) on each site. Because the same customer will have many credentials for different sites. This loses customer experience.)

I am a frappe beginner. Please guide.

Hello Did you find some sort of solutions for the Multitenant shared table?

The easiest way to achieve this is single sign-on if you want multi-site access for the same user. every site mains its own database so cross-site access with the same sign on is not possible directly using tables as each user table is unique to each database.