สอบถามเรื่อง set date format datagridview ครับ vb

Dim connection As New OleDbConnection(con)
        connection.Open()

        Dim myTable As DataTable = New DataTable("MyTable")
        myTable.Columns.Add(New DataColumn("date"))
        myTable.Columns.Add(New DataColumn("product"))
        myTable.Columns.Add(New DataColumn("channel"))
        myTable.Columns.Add(New DataColumn("position"))
        myTable.Columns.Add(New DataColumn("Impression"))
        myTable.Columns.Add(New DataColumn("Impression to use"))
        myTable.Columns.Add(New DataColumn("impression/now"))

        Dim sdate As Date
        Dim edate As Date
        sdate = CType(DateTimePicker1.Text, Date)
        edate = CType(DateTimePicker2.Text, Date)
        Try
            'Add  columns and column names to the datatable
            Dim cmd As OleDbCommand = New OleDbCommand("SELECT ch_day,P_name,ch_name,ch_posi,imp_total,imp_use,imp_now FROM Impress WHERE (Impress.ch_day>=#" & sdate & "# And Impress.ch_day<=#" & edate & "#)And (P_name='" & cbo_web.Text & "')And(ch_name='" & cbo_ch.Text & "')And(ch_posi='" & cbo_posi.Text & "') order by ch_id", connection)
            Dim dr As OleDbDataReader = cmd.ExecuteReader(CommandBehavior.Default)
            Dim myRow As DataRow
            While dr.Read()
                myRow = myTable.NewRow
                myRow.Item(0) = dr(0)   'We add the 1st value of the row to our 1st column of the datatable
                myRow.Item(1) = dr(1)
                myRow.Item(2) = dr(2)
                myRow.Item(3) = dr(3)
                myRow.Item(4) = dr(4)
                myRow.Item(5) = dr(5)
                myRow.Item(6) = dr(6)
                myTable.Rows.Add(myRow)

            End While
            dr.Close()
            'Add datatable to datagridview
            Dim myData4 As DataTable = myTable
            ds = New DataSet()
            ds.Tables.Add(myData4)
            DataGridView1.DataSource = myData4
            connection.Close()
        Catch ErrProcess As Exception
            ' MsgBox(ex.ToString)  'Show error when something goes wrong
            MessageBox.Show("ไม่สามารถคำนวณImpression จากรายการที่ท่านเลือก เนื่องจาก " & ErrProcess.Message, "ข้อผิดพลาด", MessageBoxButtons.OK, MessageBoxIcon.Warning)
            Exit Sub
        End Try