ZADANIE 15
select * from (
          select name,
                 salary,
                 dense_rank() over (order by salary desc) as rnk
          from person)
    where rnk <= 3 and rownum<=3;
ZADANIE 5
static void Insertexample()
            // inserts a new record in workplace
        {

            string cprstring;
            string companystring;
            Console.WriteLine("Indtast cpr-number");
            cprstring = Console.ReadLine();
            Console.WriteLine("Indtast company-number");
            companystring = Console.ReadLine();

            string sql;
            sql = "insert into workplace values ('"+ cprstring +  "'," + companystring + ")";
			//OracleCommand cmd = new OracleCommand();

			DbCommand cmd = dbFactory.CreateCommand();
            cmd.Connection = con;
            cmd.CommandText = sql;

			// lćs tabellen person
			try
			{   // ĺbn forbindelse til database
				con.Open();
				cmd.ExecuteNonQuery();
				Console.WriteLine("The insert is done");
			}
			catch (OracleException ex)
			{

				if (ex.Message.Contains("ORA-02291: integrity constraint (SYSTEM.CPRFOREIGN)"))
					Console.WriteLine("The cpr number does not exits");
				if (ex.Message.Contains("ORA-02291: integrity constraint (SYSTEM.COMPANYFOREIGN)"))
					Console.WriteLine("The company number does not exits");
				if(ex.Message.Contains("ORA-00001"))
					Console.WriteLine("Person already exists in company");

			}

			finally
			{   // luk forbindelse til databasen
				con.Close();
			}

            Console.WriteLine();
            Console.WriteLine("---------------------------------------------------------------------");
        }