How to find identical fields in one table in Ruby on Rails?

Question

MySQL

For example, there is an Address table with name fields.
There are two entries with the same title.
How to find two identical name-moves?
Address.where('name = name') doesn't work.

Answer 1

Address.group(:name).having('count(*) > 1') и разбор.

Answer 2

Why ask the same questions?
SELECT GROUP_CONCAT(id SEPARATOR ',') FROM Address GROUP BY name
There will be id fields separated by commas. It remains to split the line into commas and there will be line IDs