Therein lies the dilemma: your users need create/update/read/delete permissions to your entities so that they can interact with the data, but in turn, users can download the entity and see all the data in Excel. If you revoke read access, they can't pull up any data.
It's a huge security flaw if you want to use CDS for sensitive or semi-sensitive data that you don't want all your users to download. I quit making my gradebook app because of this concern.
In December, I proposed an Idea expanding permissions to include limiting access to Excel or adding more specific read access. Please upvote the idea--it should the a top priority:
I'm aware that for them to have access to specific entities through an app they will inherit access to the whole entity; agree that's not great.
However my issue is that I haven't given any users access to anything yet but they can still see all of the entities in Power Apps. How do I set it up so no one can see anything until I assign permission sets to user roles and add users to them?
Hi Mark - can you quickly check if you have granted any of the other roles like DB owner to users? If not, I'd like our team to have a look at your environment. If you could please go to https://powerapps.microsoft.com/support/ and create a new support ticket - we will have one of our team investigate.