namespace ConsoleApplication1
{
    class Program
    {
        private static readonly string connectionString1 = @"Data Source=.;Initial Catalog=Northwind;Integrated Security=True;pooling=true;";//默认值即为true，所以可省略pooling=true
        private static readonly string connectionString2 = @"Data Source=.;Initial Catalog=Northwind;Integrated Security=True;pooling=false;";
        static void Main(string[] args)
        {
            long startTicks1 = DateTime.Now.Ticks;
            using (SqlConnection conn1 = new SqlConnection(connectionString1))
            {
                for (int i = 0; i < 100; i++)
                {
                    conn1.Open();
                    conn1.Close();
                }
            }
            long endTicks1 = DateTime.Now.Ticks;
            long usedTicks1 = endTicks1 - startTicks1;
            Console.WriteLine("Used time: " + usedTicks1);

            long startTicks2 = DateTime.Now.Ticks;
            using (SqlConnection conn2 = new SqlConnection(connectionString2))
            {
                for (int i = 0; i < 100; i++)
                {
                    conn2.Open();
                    conn2.Close();
                }
            }
            long endTicks2 = DateTime.Now.Ticks;
            long usedTicks2 = endTicks2 - startTicks2;
            Console.WriteLine("Used time: " + usedTicks2);

        }

    }

}