One solution, viable only if m is very low and the clients are added manually (no online registration) is to create one environment per client, each with its own database, or to clone the original app. Both are better than creating the new table manually, because it requires no code editing, but both do require your manual intervention.
I understand that often developers need to comply rather than argue with requirements coming from the clients, but this is not black and white, we are in a gray area.
- Your app has access to all the tables, so they are not really separated
- Telling your app to access one client’s data by providing the name of the table rather than the client id for the all-clients table doesn’t make the app more secure
- A table is a way to organize data stored in a database, just like the views mentioned by @p.colbert
- Anvil tables are under the hood views of one single table, so tables don’t really exist