Check Duplicate Rows

select t.column_1,t.column_2,count(*)

from Table_Name t

having count(*)>1

group by t.column_1,t.column_2;

Example: Student table have three column id,name,age and we want to find duplicate rows for same id and name

select s.id,s.name,count(*)

from student s

having count(*)>1

group by s.id,s.name;