updating access with values in datagrid

Not able to update the table in access using the below function

Private Sub btnUpdate_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnUpdate.Click


Dim cn As New OleDbConnection(Con)
        Dim objUpdateCommand As New OleDbCommand
        Dim objDataAdapter As New OleDbDataAdapter
        cn.Open()
        Const SQLExpression As String = "UPDATE product SET Value = @pValue where owner = @powner and Item = @pItem;"
        objUpdateCommand = New 开发者_开发知识库OleDbCommand(SQLExpression, cn)

        With objUpdateCommand
            .Parameters.Add("@powner", OleDbType.VarChar, 10, "owner")
            .Parameters.Add("@pItem", OleDbType.VarChar, 8, "Item")
            .Parameters.Add("@pValue", OleDbType.VarChar, 10, "Value")
        End With

        objDataAdapter.UpdateCommand = objUpdateCommand

        MsgBox("Table Updated")

End Sub

---

Setting the updateCommand property doesn't execute the command. You need to call the update method of the table adapter.

See more info here

---

You don't have to have an adapter to just run an update statement with or without parameters. Replace your code (objDataAdapter.UpdateCommand = objUpdateCommand) with this:

Dim UpdateResultValue as Integer

UpdateResultValue = objUpdateCommand.ExecuteNonQuery

If UpdateResultValue = 0 Then
   msgbox "Table Update Failed"
Else
   msgbox "Table Updated"
End if

If you a zero is returned, it didn't work (UpdateResultValue = 0). ExecuteNonQuery is used when you are not returning values from the database tables(probably over-simplified).

---

Your parameters need to be in same order they are used in your query.