How to query for same column values?

Question

MySQL

How to check a column for unique values?

I tried this, but it's not the same: Let's say if there are 2 or more entries in the response column with the content, for example: hello , or any other. How to make a request and return a true or false response?
SELECT COUNT(*) FROM chats WHERE response > 2

Answer 1

You write in the address bar of your browser: find duplicate values ​​in the database
If you want to get an answer from toaster users, then add site:qna.habr.com