Excel Script to match common values and copy to the corresponding cell

Question

I've seen similar questions but not this exact thing which I'm stuck on.

Above is a sample of the data i'm working with.

The left column (E) of email addresses is quite long 10,000+ and is in no particular order, with it's corrasponding country (F).
The right column of email addresses (H) is a fraction of the size however it contains many duplicate values.

I need to compare all of the values in E with all of the values in H , if there is a match copy the value in F to the corresponding value in I .

I've looked into Vlookup, VBA scripts and if formulas but I can't get my head around what I need to do here. Any help would be appreciated.

Please and thanks.

Answer 1

Please, try the next code. It uses arrays and working mostly in memory should be very fast:

Sub ExtractMatchingCountry()
 Dim sh As Worksheet, lastRowE As Long, lastRowH As Long, arrEF, arrHI, i As Long, j As Long
 
 Set sh = ActiveSheet
 lastRowE = sh.Range("E" & sh.rows.count).End(xlUp).Row 'last cell in E:E
 lastRowH = sh.Range("H" & sh.rows.count).End(xlUp).Row 'last cell in H:H
 
 arrEF = sh.Range("E2:F" & lastRowE).value 'place the range in an array for faster iteration/processing
 arrHI = sh.Range("H2:I" & lastRowH).value 'place the range in an array for faster iteration/processing
 
 For i = 1 To UBound(arrEF)
    For j = 1 To UBound(arrHI)
        If arrEF(i, 1) = arrHI(j, 1) Then
            arrHI(j, 2) = arrEF(i, 2): Exit For
        End If
    Next j
 Next i
 'drop the processed array content to the range:
 sh.Range("H2").Resize(UBound(arrHI), 2).value = arrHI
End Sub

Is there a possibility that the strings to be compared to look the same but some letters to be in Upper case against Lower? If so, I can adapt the code to handle such a situation, too. Now, it compares the identic strings . I mean "john.doe@yahoo.com" is not the same with "John.doe@yahoo.com"...