How to find duplicate values using SQL

Assume, Table sample contains 3 rows

select * from sample;
+----+------------+
| id | Name       |
+----+------------+
|  1 | xyz        |
|  2 | Rajesh     |
|  3 | Rajesh     |
+----+------------+

Select name,count(*) from sample group by name;

The above query will group all the similar name
value into a group,count(*) will list the number
of counts for the value in the group.

+------------+----------+
| Name       | count(*) |
+------------+----------+
|Rajesh      |        2 |
| ABC        |        1 |
+------------+----------+

Now we can able to identify the duplicate rows,
 but how to list the
duplicate rows alone.


Select Name,count(*) from sample group by
name having count(*) > 1;

+------------+----------+
| Name       | count(*) |
+------------+----------+
|Rajesh      |        2 |
+------------+----------+
As we know duplicate rows has the count greater
than 1. So we are using the Having clause to
check which group contains the counts greater than 1