//------------- Get Students than belong to more than one Courses
public static List <StudentCourses> GetStudentCourses()
{
List <StudentCourses> studentCourses = new List <StudentCourses>();
string query = "select concat(FirstName,' ', LastName) as Student, " +
"Count(s.StudentId) as NumberOfCourses from Student s " +
"inner join CourseStudent cs on cs.StudentId = s.StudentId " +
"group by LastName, FirstName having Count(s.StudentId) > 1";
using (SqlConnection con = new SqlConnection(ConString))
{
con.Open();
SqlCommand sqlCommand = new SqlCommand(query, con);
SqlDataReader reader = sqlCommand.ExecuteReader();
int count = 0;
while (reader.Read())
{
count++;
string student = reader[0].ToString();
int numberOfCourses = Convert.ToInt32(reader[1].ToString());
StudentCourses SC = new StudentCourses(count, student, numberOfCourses);
studentCourses.Add(SC);
}
}
return(studentCourses);
}
public static void ExportData()
{
ShowExportData();
string input = CheckCorrectValueExporttMenu();
if (input == "1")
{
//Students List
Student.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "2")
{
//Trainers List
Trainer.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "3")
{
//Assignmgents List
Assignment.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "4")
{
//Courses List
Course.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "5")
{
//Students Per Course
StudentPerCourse.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "6")
{
//Trainers Per Course
TrainerPerCourse.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "7")
{
//Assignments Per Course
AssignmentPerCourse.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "8")
{
//Assignments Per Course Per Student
AssignmentPerCoursePerStudent.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "9")
{
//Students than belong to more than one Courses
StudentCourses.Output();
Exit.CheckToExitFolderSyntetic();
}
else if (input == "10")
{
//Exit
Exit.CheckToExitFolderSyntetic();
}
}