我建两个表单，在form1 从access里读取数据并显示，在form2里向access里写数据，现在出现一个问题，在form2里向access插入一条记录的时候，没有报错，但是在form1里有事能读出放写进去的数据，有时候就不能读出来；再打开access文件，里面什么数据都没有，请问各位大神，这是什么原因呀？我插入记录的代码如下：
Dim connectionString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\bwl.accdb"

Dim myconn As New OleDbConnection(connectionString)

myconn.Open()

Dim mySQL As String = "INSERT INTO bwl (riqi,dbsj) VALUES ('" & DateTimePicker1.Value & "','" & TextBox1.Text & "')"

Dim objCmd As New OleDbCommand(mySQL, myconn)
   
objCmd.ExecuteNonQuery()

myconn.Close()

Me.Close()

Dim connectionString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\bwl.accdb"
Dim myconn As New OleDbConnection(connectionString)
Private Sub oledbdap()
        '自定义数据集填充代码！
        strCom = " SELECT * FROM tt"
        Dim myCommand As OleDb.OleDbDataAdapter = New OleDb.OleDbDataAdapter(strCom, OleDbConnection1)
        myCommand.Fill(myDataSet, strCom)
    End Sub
Dim myDataSet As New DataSet   '自定数据集
    Dim strCom As String  
  Dim cmd As New OleDb.OleDbCommand   '自定义连接命名代码
    Dim strSql As String                '自定义连接命名数据库表
    Private Sub oledbcom()
        '自定义COM命名代码！
        Dim cmd As New OleDb.OleDbCommand
        strSql = "SELECT * FROM tt"
         = strSql
        cmd.Connection = Me.OleDbConnection1
    End Sub
 oledbdap()   '填充代码
myconn.Open()
dim row as datarow
row=myDataSet.tables(0),nowrow
row("字段")="相应数据库"
……
oledbdap.updata(mydataset,tt)
myconn.Close()