How to find duplicate last names using Levenshtein distance?

Question

MySQL

How to find duplicates in the Clients table with last_name surnames, having a custom Levenstein function?
The distance should not exceed 2. It turns out that you need to compare each surname with the rest. I can't figure out how it's done in SQL.

Answer 1

select client.last_name
from clients client
inner join clients other_client on levenshtein(client.last_name, other_client.last_name)<=2;

Not?