How to find duplicates in 2 columns not 1

Question

I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having th

Answer 1

To find the duplicates:

select stone_id, upcharge_title from tablename group by stone_id, upcharge_title having count(*)>1

To constrain to avoid this in future, create a composite unique key on these two fields.