I need help avoiding duplicates

[dadams25]

i have a workbook that has lots of the identical sheet copied and renamed to employees for accountability purposes. i put an order number in column "L" on all of the sheets. how can i go about getting the word "duplicate" to populate in column "M" on the same row when the same order number is already in the workbook.

putting all of the data on the same sheet instead of separate sheets is not an option. some have told me that i would need to use a macro but i do not know how to write a macro.

anyone able to help me out of this issue?

 

[MDCurry]

Based on my understanding:
Assume you have 3 sheets (named Sheet 1, Sheet 2, Sheet3) and data starts at cell L2
Enter this formula in cell M2 and copy down

=IF(COUNTIF(Sheet1!L:L,L2)+COUNTIF(Sheet2!L:L,L2)+COUNTIF(Sheet3!L:L,L2)>1,"Duplicate","")

If you have more sheets will need to add more countif

 

[dadams25]

this brings up a update values dialog box.

 

[b.downey]

Place the following code in a VBA Module and execute. It will mark the Duplicate Orders from Column "L" with the "Dup" tag in column "M". It will also provide a number representing the number of times this Order number has been encoundered.

Not that the first occurance of the Order Number is not maked as a "Dup"

Option Explicit
Type RecType
    OrderNumber As String
    Cnt As Long
End Type
Dim Rec() As RecType
Function FindDups()
    Dim ws As Worksheet
    Dim wsNo As Integer
    Dim RowNo As Long
    Dim Idx As Long
    
    ReDim Rec(0)
    
    For wsNo = 1 To ThisWorkbook.Worksheets.Count
        Set ws = ThisWorkbook.Worksheets(wsNo)
    
        For RowNo = 2 To ws.UsedRange.Rows.Count
            Idx = FindOrdNoIdx(ws.Cells(RowNo, 12)) 'Column 'L' is 12
            If Rec(Idx).Cnt > 1 Then
                ws.Cells(RowNo, 13) = "Dup " & Rec(Idx).Cnt
            Else
                ws.Cells(RowNo, 13) = ""
            End If
                
        Next RowNo
        
    Next
End Function
Function FindOrdNoIdx(OrderNo As String) As Long
    Dim I As Long
    For I = 1 To UBound(Rec)
        If Rec(I).OrderNumber = OrderNo Then
            FindOrdNoIdx = I
            Rec(I).Cnt = Rec(I).Cnt + 1
            Exit Function
        End If
    Next I
        
    ReDim Preserve Rec(I)
    Rec(I).OrderNumber = OrderNo
    Rec(I).Cnt = 1
    FindOrdNoIdx = I
End Function

 

[dadams25]

thanks guys. i got it to go