vb.net 向数据库插入记录不行为什么？

Imports System.Data.OleDb
Public Class main
 Private Sub main_Load(sender As Object, e As EventArgs) Handles MyBase.Load
       Static cn As OleDbConnection
        Static da As OleDbDataAdapter
        Static ds As DataSet
        
        Static cnStr As String
        cnStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=E:\tools\MyFile\Assessment\Assessment\data.mdb;Persist Security Info=False"

        cn = New OleDbConnection(cnStr)
        Dim sql As String
        sql = "select * from User_tbl"
        da = New OleDbDataAdapter(sql, cn)
        ds = New DataSet
        da.Fill(ds, "User_tbl")
        DataGridView1.DataSource = ds.Tables(0)


        Static Name As String
        Static pwd As String
        Name = "sdfs"
        pwd = "sdfs"


        'cn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=E:\tools\MyFile\Assessment\Assessment\data.mdb;Persist Security Info=False")
        cn.Open()
        Static sd As String
        sd = "insert into User_tbl (ID,name,pwd) values('" & "','" & Name & "','" & pwd & "'')"
        Static cm = New OleDbCommand(sd, cn)
        'cm.ExecuteNonQuery()

        cn.Close()
        MessageBox.Show("保存成功！！！")

    End Sub

End Class
这是代码？