Это группировка по одной колонке. Сделал на C# и на примере List<Student> 
| Код |
public class Student
{
public string Curs { get; private set; }
public string Surname { get; private set; }
public string Firstname { get; private set; }
public string Patronymic { get; private set; }
public int yearBirthday { get; private set; }
public Student(string curs, string surname, string firstname, string patronymic, int year)
{
this.Curs = curs;
this.Surname = surname;
this.Firstname = firstname;
this.Patronymic = patronymic;
this.yearBirthday = year;
}
}
class Program
{
static void Main(string[] args)
{
List<Student> students = new List<Student>()
{
new Student("первый", "Иванов","Иван", "Петрович", 1980),
new Student("первый", "Иванов", "Иван", "Петрович", 1980),
new Student("второй", "Петров", "Петр" , "Петрович", 1996),
new Student("второй", "Петров", "Сидор", "Иванович", 1997),
new Student("третий", "Сидоров", "Петр", "Иванович", 1995),
new Student("первый", "Иванов", "Сидор", "Сидоров", 1997),
new Student("второй", "Сидоров", "Иван", "Иванович", 1996)
};
var studentCurses = students.GroupBy(s => s.Curs)
.Select(g => new
{
Curs = g.Key,
SurnameCount = g.Select(s=>s.Surname).Distinct().Count(),
FirstnameCount = g.Select(s=>s.Firstname).Distinct().Count(),
Patronymic = g.Select(s=>s.Patronymic).Distinct().Count(),
Year = g.Select(s=>s.yearBirthday).Distinct().Count()
});
foreach (var curs in studentCurses)
{
Console.WriteLine("{0} {1} {2} {3} {4}", curs.Curs,
curs.SurnameCount,
curs.FirstnameCount,
curs.Patronymic,
curs.Year);
}
}
}
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