I use VB6.0 to access an Oracle DB for mapping purposes, I cannot help you with the udl file, but I can show you an example of my code.

I regularly use the datadesiger/connect objects to open a recordset. An example of my code is below (to use this code you must add and define your oracle database connection using a data designer named DataEnvironment1).

Dim cnn As ADODB.Connection
Dim rs As ADODB.Recordset
Dim objFindResults As MapPointCtl.FindResults
Dim objPushpin As MapPointCtl.Pushpin
Dim objMap As MapPointCtl.Map

Set objMap = mapform.themap.ActiveMap

'##### Open data connection to Oracle #####

Set cnn = DataEnvironment1.Connection1

If cnn.State = adStateClosed Then
cnn.Open
End If

'##### Check if record currently exists in DB #####

Set rs = New ADODB.Recordset

rs.Source = "select * from main"
Set rs.ActiveConnection = cnn
rs.Open

rs.MoveFirst
Do Until rs.EOF

Set objFindResults = objMap.FindAddressResults(rs!Address, _
rs!City, , rs!State, rs!zipcode, geoCountryUnitedStates)

If objFindResults.ResultsQuality = geoFirstResultGood Then
Set objLoc = objFindResults.Item(1)
end if

Set objPushpin = objMap.AddPushpin(objLoc, _
rs!Retailer_number & " " & _
rs!Business_name)

loop

rs.Close
cnn.Close

Set cnn = Nothing
Set rs = Nothing