At the moment I am working on a solution with the Main Topic in the 'Data' table. I already started on it and I think it is better in my current case. But I will look into your solution also. You never know if it is useful in another case and it never hurts to dabble. (I once implemented Fibonacci Numbers with streams, just for the sake of it.) I really do not like the last part, where after a delete the oldest becomes the new main. I was wondering about the isMain in the UNIQUE indexes. I will share my dabbles later on.