My data is as follows:

const data = {
  papers: {
    id1: {
      name: 'test',
      annotated: {
        user1: true,
        user2: true,
      },
    },
  },
};

I want to return all papers that their annotated field does not contain the key "user1". How can I run such a query in a real-time database firebase? If it is not possible do you have any idea to restructure data in order to I can run such a query on this database?