modify to two fields instead of one PLEASE Help

[deb]

I found a link via this forum to Prevent dupes entered by a form

http://www.databasedev.co.uk/duplicates.html ; It works great!!!

However I need help in making it check two fields instead of one.
The below code checks for a duplicate record with a specific dtID. i.e.
Jun07=6 dtID
I have many project with this dtID. I need it to check for the DtID and
ProjectID. To make sure there is not a dupe for ProjectID=4 with DtID =6.

I am desperate for help
Please help. I am just learing VBA, and I am no so good yet.

Private Sub ReportDtID_BeforeUpdate(Cancel As Integer)
Dim DtID As String
Dim stLinkCriteria As String
Dim rsc As DAO.Recordset

Set rsc = Me.RecordsetClone

DtID = Me.ReportDtID.Value
stLinkCriteria = "[ReportDtID]=" & DtID
'Check table for duplicate ID
If DCount("ReportDtID", "tCustImpacts", _
stLinkCriteria) > 0 Then
'Undo duplicate entry
Me.Undo
'Message box warning of duplication
MsgBox "Warning Customer Impact for selected Report Date was
previously entered." _
& vbCr & "You will now been taken to the record." _
& vbCr & vbCr & "Verify the Report Date and make changes(as
needed).", _
vbInformation, "Duplicate Information"

If Me.ReportDtID = 1 Then
Me.Undo
DoCmd.DoMenuItem acFormBar, acEditMenu, 8, , acMenuVer70
DoCmd.DoMenuItem acFormBar, acEditMenu, 6, , acMenuVer70
End If

'Go to record of original ID
rsc.FindFirst stLinkCriteria
Me.Bookmark = rsc.Bookmark
Forms!f2CustImpactsEdit.Form!f2CustImpactsEditDetails.Form.Visible =
True

End If

Set rsc = Nothing

End Sub

 

[SydneyGeek]

Deb, you can go down the route of checking for 2 fields but you may find it easier to create a compound primary key.

You will need to:
1. In a query, check for any duplicates (you can do this with a concatenated field, then count the occurrences).
2. Once this is clean, go to the table design. Ctrl-click the 2 fields, then select the Primary Key symbol. This will prevent users from duplicating the combination, without any code required from you. It will also force them to enter data into both fields, so you won't have gaps in your data.

Denis