Find duplicate records in MySQL

Question

I want to pull out duplicate records in a MySQL Database. This can be done with:

SELECT address, count(id) as cnt FROM list
GROUP BY address HAVING cnt >         


        

Answer 1

select address from list where address = any (select address from (select address, count(id) cnt from list group by address having cnt > 1 ) as t1) order by address

the inner sub-query returns rows with duplicate address then the outer sub-query returns the address column for address with duplicates. the outer sub-query must return only one column because it used as operand for the operator '= any'