Load aggregate data from Excel into ADODB.RecordSet - excel

Question

I am trying to load data from an Excel file in a specific sheet into an ADODB.RecordSet via a VBA macro by using SQL SELECT command.
There are several columns on the Excel sheet, and I don't need all of them.
For example:
col.A = Surname, col.B = Name, col.C = IDPerson, [....columns that are not needed], Col.N = Boss
The purpose would be to get a recordset of aggregated data for:
col.C = IDPerson, col.N = Boss.
The fields highlighted in the image below.
I would like to have a RecordSet with the aggregated (non-repeating) data of the columns highlighted in yellow.
Obviously, this problem could also be solved by loading a matrix, but, in this case I would have to build a loading algorithm to "clean" any repetitions in the data and then later I would have to provide a search function with some loops.
So I thought that if I could load all the data I need by reading the WorkSheet as if it were a data table and then make a query on it to extract the data that I need and load everything in an ADODB.RecordSet would be much more efficient also for searching for data (filter data for example).
Below I report my code that loads all the data of my sheet:
Public Sub LoadRecordSet(ByVal LastRow As Long, ByVal LastCol As Integer)
Dim cnt As ADODB.Connection
Dim rsData As ADODB.Recordset
Dim strSQL As String
Dim strTMP As String
strTMP = Cells(LastRow, LastCol).Address
strTMP = Replace(strTMP, "$", "")
Set cnt = New ADODB.Connection
cnt.Mode = adModeRead
cnt.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;" & _
"Data Source=" & ActiveWorkbook.FullName & ";" & _
"Extended Properties=""Excel 12.0 Macro;HDR=Yes;"";"
cnt.Open
strSQL = "SELECT * FROM [Sheet1$C2:" & strTMP & "]"
Set rsData = New ADODB.Recordset
With rsData
Set .ActiveConnection = cnt
.Source = strSQL
.CursorLocation = adUseClient
.CursorType = adOpenKeyset
.LockType = adLockOptimistic
.Open
End With
'TODO - Something with rsData for filtering or to research
'GC
If Not rsData Is Nothing Then
If rsData.State <> adStateClosed Then rsData.Close
Set rsData = Nothing
End If
If Not cnt Is Nothing Then
If cnt.State <> adStateClosed Then cnt.Close
Set cnt = Nothing
End If
End Sub
My question is: "What if I just want to load some columns as described above and aggregate them so they don't have repetitions in the data?"
For example if I want to load similar
SELECT [cod.fiscale], responsabile FROM [MySheet$A3:N480] GROUP BY [cod.fiscale], responsabile
It's possible?
Thank you so much.

Answer 1

I improved my code which is now working:
Public Sub CaricaDati()
Dim cnt As ADODB.Connection
Dim rsDati As ADODB.Recordset
Dim strSQL As String
Dim strTMP As String
Dim i As Integer
on Error GoTo Error_Handler
Range("A3").Select
g_BOLTS_UltimaRiga = LasRow
Call LastCol
strTMP = Cells(g_LastRow, g_LastCol).Address
strTMP = Replace(strTMP, "$", "")
Set cnt = New ADODB.Connection
cnt.Mode = adModeRead
cnt.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;" & _
"Data Source=" & ActiveWorkbook.FullName & ";" & _
"Extended Properties=""Excel 12.0 Macro;HDR=Yes;"";"
cnt.Open
'strSQL = "SELECT * FROM [2$C2:" & strTMP & "]"
strSQL = "SELECT cf, responsabile FROM [2$C2:" & strTMP & "] GROUP BY cf, responsabile"
Set rsDati = New ADODB.Recordset
With rsDati
Set .ActiveConnection = cnt
.Source = strSQL
.CursorLocation = adUseClient
.CursorType = adOpenKeyset
.LockType = adLockOptimistic
.Open
End With
If Not (rsDati.BOF And rsDati.EOF) Then
strTMP = ""
For i = 0 To rsDati.Fields.Count - 1
strTMP = strTMP & rsDati.Fields(i).Name & ";"
Next i
Debug.Print strTMP
strTMP = ""
rsDati.MoveFirst
Do While Not rsDati.EOF
strTMP = ""
For i = 0 To rsDati.Fields.Count - 1
strTMP = strTMP & rsDati.Fields(i).Value & ";"
Next i
Debug.Print strTMP
rsDati.MoveNext
Loop
End If
Uscita:
On Error Resume Next
'GC
If Not rsDati Is Nothing Then
If rsDati.State <> adStateClosed Then rsDati.Close
Set rsDati = Nothing
End If
If Not cnt Is Nothing Then
If cnt.State <> adStateClosed Then cnt.Close
Set cnt = Nothing
End If
Exit Sub
Error_Handler:
On Error GoTo 0
MsgBox Err.Number & " - " & Err.Description, vbOKOnly + vbCritical, "ERRORE IMPREVISTO"
GoTo Uscita
End Sub