Abusing Excel VBA... to maintain data stored in a database

I need to build a little UI to allow easy maintenance of some data stored in a MySQL database, and the end user wants to do that in Excel (I know, I know).

The code I came up with comes pretty close to what I'd call Model-View-Presenter (MVP).

I can get my form shown like this:

set x = new CustomerGroupsPresenter set x.Command = new SqlCommand x.Show 

Obviously this code uses the SqlCommand ADODB wrapper that I've written earlier (for VB6), reviewable here.

Here's the form's code-behind:

Public Event CloseCommand(ByVal sender As CustomerGroupsView) Public Event EditCustomerGroupCommand(ByVal id As Long, ByVal description As String) Public Event AddCustomerGroupCommand() Public Event DeleteCustomerGroupCommand(ByVal id As Long) Option Explicit Private Sub AddCustomerGroupButton_Click() RaiseEvent AddCustomerGroupCommand End Sub Private Sub CloseButton_Click() RaiseEvent CloseCommand(Me) End Sub Private Sub CustomerGroupsList_Change() DeleteCustomerGroupButton.Enabled = Not (CustomerGroupsList.ListIndex = -1) End Sub Private Sub CustomerGroupsList_DblClick(ByVal Cancel As MSForms.ReturnBoolean) Dim selectedRecord() As String selectedRecord = Split(CustomerGroupsList.List(CustomerGroupsList.ListIndex), StringFormat("\t")) Dim id As Long id = CLng(selectedRecord(0)) Dim description As String description = selectedRecord(1) RaiseEvent EditCustomerGroupCommand(id, description) End Sub Private Sub DeleteCustomerGroupButton_Click() Dim selectedRecord() As String selectedRecord = Split(CustomerGroupsList.List(CustomerGroupsList.ListIndex), StringFormat("\t")) Dim id As Long id = CLng(selectedRecord(0)) RaiseEvent DeleteCustomerGroupCommand(id) End Sub 

..and the Presenter class:

Private cmd As SqlCommand Private WithEvents vwCustomerGroups As CustomerGroupsView Option Explicit Public Property Get Command() As SqlCommand Set Command = cmd End Property Public Property Set Command(ByRef value As SqlCommand) Set cmd = value End Property Public Sub Show() Set vwCustomerGroups = New CustomerGroupsView RefreshCustomerGroups vwCustomerGroups.Show vbModal End Sub Private Function View() As CustomerGroupsView Set View = vwCustomerGroups End Function Private Sub RefreshCustomerGroups() vwCustomerGroups.CustomerGroupsList.Clear Dim sql As String sql = "SELECT Id, Description FROM Planning.CustomerGroups ORDER BY Id;" Dim groups As SqlResult Set groups = cmd.QuickExecute(sql) groups.ValueSeparator = StringFormat("\t") Dim group As SqlResultRow For Each group In groups vwCustomerGroups.CustomerGroupsList.AddItem group.ToString Next End Sub Private Sub vwCustomerGroups_AddCustomerGroupCommand() Dim description As String description = InputBox("Please enter a description for the new CustomerGroup:", "Edit", "(new customer group)") If StrPtr(description) = 0 Or description = vbNullString Then Exit Sub Dim sql As String sql = "INSERT INTO Planning.CustomerGroups (Description, DateInserted) VALUES (?, ?);" Dim success As Boolean success = cmd.QuickExecuteNonQuery(sql, description, Now) If Not success Then MsgBox "Insert operation failed!", vbExclamation, "Warning" RefreshCustomerGroups End Sub Private Sub vwCustomerGroups_CloseCommand(ByVal sender As CustomerGroupsView) sender.Hide End Sub Private Sub vwCustomerGroups_DeleteCustomerGroupCommand(ByVal id As Long) Dim sql As String sql = "SELECT COUNT(*) FROM Planning.Customers WHERE CustomerGroupId = ?;" Dim childRecords As Long childRecords = CLng(cmd.QuickSelectSingleValue(sql, id)) If childRecords > 0 Then MsgBox StringFormat("This CustomerGroup has {0} customer(s) associated to it and cannot be deleted.", childRecords), vbExclamation, "FK Constraint violation!" Exit Sub End If If MsgBox(StringFormat("Delete CustomerGroup #{0}?\n(this cannot be undone!)", id), vbExclamation + vbYesNo, "Please confirm") = vbNo Then Exit Sub sql = "DELETE FROM Planning.CustomerGroups WHERE Id = ?;" Dim success As Boolean success = cmd.QuickExecuteNonQuery(sql, id) If Not success Then MsgBox "Delete operation failed!", vbExclamation, "Warning" RefreshCustomerGroups End Sub Private Sub vwCustomerGroups_EditCustomerGroupCommand(ByVal id As Long, ByVal description As String) Dim newDescription As String newDescription = InputBox(StringFormat("Please enter a new description for CustomerGroup ID#{0}:", id), "Edit", description) If StrPtr(newDescription) = 0 Then Exit Sub Dim sql As String sql = "UPDATE Planning.CustomerGroups SET Description = ?, DateUpdated = ? WHERE Id = ?;" Dim success As Boolean success = cmd.QuickExecuteNonQuery(sql, newDescription, Now, id) If Not success Then MsgBox "Update operation failed!", vbExclamation, "Warning" RefreshCustomerGroups End Sub 

I feel like I could move the SQL outside the Presenter class and into some data service class.. but would that be overkill?

Besides the missing error-handling, what's there to say about this code?