Koding UBAH / UPDATE pada vb.net access

Koding UBAH / UPDATE vb.net
Sebelumnya memang pernah nulis koding ubah, cari aja di
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sekarang kamu bisa cobain koding ini juga ya...

    Private Sub bubah_Click(sender As Object, e As EventArgs) Handles bubah.Click
        If tid.Text = "" Then
            MsgBox("ID BELUM DIISI", MsgBoxStyle.Information, "INFORMASI")
            Exit Sub
        End If
        cmd = New OleDbCommand("SELECT * from buku where idbuku = ' " & tid.Text & " ' ", conn)
        dr = cmd.ExecuteReader
        dr.Read()
        If dr.HasRows Then
            Dim update As String = "update buku set judul ='" & tjudul.Text & "', penulis ='" & tpenulis.Text & "', penerbit ='" & tpenerbit.Text & " ' where idbuku = ' " & tid.Text & " ' "
            cmd = New OleDbCommand(update, conn)
            cmd.ExecuteNonQuery()
            Call tampil()
            Call kosong()
        End If
    End Sub