SQL relational database

It seems like the SQL terminal get stuck.
How to unstuck it?

Can you explain what you mean by “stuck”?

Assuming stuck simply means that it isn’t letting you move on w/ the correct answer, you can try a few things:

  • try trypingexit in the terminal to reset it. This usually works for me when the correct answer is not being accepted.
  • try resetting that lesson / tutorial. this solution would be solid since you know the command you need to type is simply clear so you could reset and move on if need be
    -try another browser / computer
    -give the lesson some time.

Since you’re on the Beta course, I think the FCC people should at least point you to this documentation they’ve prepared for situations like this:
Running the Relational Database Curriculum in your Browser - Backend Development - The freeCodeCamp Forum