พี่ค่ะช่วยหน่อยค่ะ โปรแกรมมันทึกข้อมูลไม่ได้นะค่ะ มันขึ้น"The changes you requested were not successful because they would create duplicate values in the index, primary key, or relationship. Change the data in the field or fields that contain duplicate da

Private Sub btnSaveList_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSaveList.Click

        If txtID_E.Text = "" Then
            MessageBox.Show("กรุณาระบุรหัสพนักงานก่อน !!!", "ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Information)
            txtID_E.Focus()
            Exit Sub
        End If

        If lsvProductsList.Items.Count = 0 Then
            MessageBox.Show("กรุณาป้อนรายการสั่งซื้ออุปกรณ์ !!!", "ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Information)
            txtID_P.Focus()
            Exit Sub
        End If

        Dim sqlOrder As String = ""
        Dim comOrder As OleDbCommand = New OleDbCommand

        With Conn
            If .State = ConnectionState.Open Then .Close()
            .ConnectionString = strConn
            .Open()
        End With

        Try
            If MessageBox.Show("คุณต้องการบันทึกรายการการสั่งซื้ออุปกรณ์ ใช่หรือไม่?", "คำยืนยัน", MessageBoxButtons.YesNo, MessageBoxIcon.Question) = Windows.Forms.DialogResult.Yes Then

                AutoGenerateNo_O()

               


                With comOrder
                    .CommandType = CommandType.Text
                    .CommandText = sqlOrder
                    .Connection = Conn
                    .ExecuteNonQuery()
                End With

                Dim i As Integer = 0

                Dim tmpID_P As String = ""
                Dim tmpNumber_O As Integer = 0

                Dim sqlProducts As String = ""
                'Dim tmpRemain_P As Integer = 0
                'Dim tmpNumber_W As Integer = 0
                'Dim tmpNumber_approval As Integer = 0
                Dim tmpDateOrder As Date
                tmpDateOrder = Date.Now

                For i = 0 To lsvProductsList.Items.Count - 1
                    sqlOrder = "INSERT INTO t_Order (Order_id,Order_Date,Order_PriceTotal,Employee_id,Product_id,Order_Quantity) "
                    sqlOrder &= " VALUES('" & LastID_O & "',"
                    sqlOrder &= "'" & dtpDateOrder.Value & "',"
                    sqlOrder &= "'" & lblTotal.Text & "',"
                    sqlOrder &= "'" & txtID_E.Text & "')"
                    sqlOrder &= "'" & tmpID_P & "',"
                    sqlOrder &= tmpNumber_O & ")"
                    tmpID_P = lsvProductsList.Items(i).SubItems(0).Text
                    sqlOrder = "INSERT INTO t_Order(Product_id,Order_Quantity)"

                    tmpNumber_O = CInt(lsvProductsList.Items(i).SubItems(3).Text)
                  


                    With comOrder
                        .CommandText = sqlOrder
                        .ExecuteNonQuery()
                    End With

                Next

                frmMain.tslStatus.Text = "กำลังบันทึกข้อมูล..."
                MessageBox.Show("บันทึกรายการการสั่งซื้ออุปกรณ์เรียบร้อยแล้ว !!!", "ผลการทำงาน", MessageBoxButtons.OK, MessageBoxIcon.Information)
                frmMain.tslStatus.Text = ""

                If IsInstallPrinter() = True Then
                    If prDlg.ShowDialog = Windows.Forms.DialogResult.OK Then
                        prDoc.Print()
                    End If
                Else
                    MessageBox.Show("กรุณาติดตั้งเครื่อง Printer ก่อนสั่งพิมพ์เอกสาร", "ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Information)

                End If

                ClearAllEmployeesData()
                ClearAllProductsData()

                lsvProductsList.Items.Clear()

                txtID_E.Enabled = True
                txtID_E.Focus()
            End If
        Catch ErrProcess As Exception
            MessageBox.Show("ไม่สามารถบันทึกรายการการสั่งซื้อได้ เนื่องจาก " & ErrProcess.Message, "ข้อผิดพลาด", MessageBoxButtons.OK, MessageBoxIcon.Warning)
            Exit Sub
        End Try
    End Sub

มันเกี่ยวกับตรงนี้ด้วยไหมค่ะ
  Private Sub AutoGenerateNo_O()
        Dim sqlTmp As String = ""
        Dim comTmp As OleDbCommand = New OleDbCommand
        Dim drTmp As OleDbDataReader
        Dim tmpID_O As Integer = 0

        sqlTmp = "SELECT TOP 1 Order_id FROM t_Order ORDER BY Order_id DESC"

        With Conn
            If .State = ConnectionState.Open Then .Close()
            .ConnectionString = strConn
            .Open()
        End With

        Try
            With comTmp
                .CommandType = CommandType.Text
                .CommandText = sqlTmp
                .Connection = Conn
                drTmp = .ExecuteReader()

                drTmp.Read()

                tmpID_O = CInt(CStr((drTmp.Item("Order_id"))))
                tmpID_O = tmpID_O + 1
                LastID_O = tmpID_O.ToString("00000")
            End With
        Catch
            LastID_O = "00001"
        End Try
    End Sub