连接池的作用。(差距咋这么大泥？)

今天测试了一下是否使用数据库连接池到底能有多大的差别，下面是测试结果(代码附在最后面，使用Visual Basic 2005)：

下面这个是没有使用连接池的：

这就是差距啊～～～

Imports System.Data
Imports System.Data.SqlClient


Public Class Form1

    Dim conBuilder As New SqlConnectionStringBuilder
    Dim con As New SqlConnection

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        conBuilder.DataSource = "10.10.10.10"
        conBuilder.InitialCatalog = "NorthWind"
        conBuilder.UserID = "sa"
        conBuilder.Password = "sa"

    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If CheckBox1.CheckState = CheckState.Checked Then
            conBuilder.Pooling = False
        Else
            conBuilder.Pooling = True
        End If

        con.ConnectionString = conBuilder.ConnectionString
        Dim ti As Integer
        Dim wa As New System.Diagnostics.Stopwatch
        wa.Start()
        For i As Integer = 0 To 100
            con.Open()
            con.Close()
        Next
        wa.Stop()
        ti = wa.ElapsedMilliseconds
        Label2.Text = ti

    End Sub
End Class