How to print duplicate rows in a table?

In the above table, we can find duplicate row using below query.

SELECT name, section FROM tbl
GROUP BY name, section
HAVING COUNT(*) > 1

Another Example:
Given a table named PERSON task is to write an SQL query to find all duplicate name in the table.
Example :

+----+---------+
| Id | NAME    |
+----+---------+
| 1  | Geeks   |
| 2  | for     |
| 3  | Geeks   |
+----+---------+

Output :
+---------+
| NAME    |
+---------+
| Geeks   |
+---------+

The simple approach is to make a temporary table which have count of all the names in a table.

Duplicated NAME existed more than one time, so to count the times each NAME exists, we can use the following code:

select NAME, count(NAME) as num
from Person
group by NAME;

| NAME    | num |
|---------|-----|
| Geeks   | 2   |
| for     | 1   |

This is a temporary table, on which we can run the below code to get duplicate NAME.

select NAME from
(
  select NAME, count(NAME) as num
  from Person
  group by NAME
) as statistic
where num > 1;

The Best approach is to use GROUP BY and HAVING condition. It is more effective and faster then previous.

MySql :

select NAME
from Person
group by NAME
having count(NAME) > 1;

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