ShopDB shopDB = new ShopDB();
var employeesTableAdapter = new ShopDBTableAdapters.EmployeesTableAdapter();
employeesTableAdapter.Fill(shopDB.Employees);

var ordersTableAdapter = new ShopDBTableAdapters.OrdersTableAdapter();
ordersTableAdapter.Fill(shopDB.Orders);

ShopDB.EmployeesDataTable employees = employeesTableAdapter.GetData();
employees.Columns.Add("AggregatedColumn", typeof(double),"String expression(COUNT)");

 foreach (DataRow employeeRow in employees.Rows)
        {
            foreach (DataColumn employeeColumn in employees.Columns)
                Console.WriteLine("{0}: {1}", employeeColumn.ColumnName, employeeRow[employeeColumn]);