Questions about Privacy, data rules

Hi there,

I’m pretty new in bubble. I have two questions regarding the privacy top:

  1. What is the different between ‘Current User’ and ‘This User’?

  2. I have a database which includes message_receiver, message_sender and message_content. Now I want to ensure, that only both of them are able to access to their messages.
    Is that the correct rule for it?
    WhenThis Message’s Creator is Current User or This Message’s Message receiver is Current User
    Anyone else can see/do nothing

  3. In the User Table, I store the User data and also usernames of his or her friends, field ‘matched_users’ . How can I ensure, that they only can access to the own data and also to the data of their matched users?

Thank your so much for your hints
Cheers Marco