Owen Rumney

Software Engineer

As part of a project I’m working on I need to create a cross join of users against symbols; the idea being that any of the given users might look at any of the given symbols. I have a list of users and a list of symbols which I essentially need a cross-join on.

For this example I’ll use cars and engine/transmission variants.


From these two lists I need to quickly create all possible combinations;

cross-joined list

I can’t find any function that will do what I was so I’ve created a VBA function that will do it;

Function CrossJoin(r1 As Range, r2 As Range) As Variant
    Dim size As Integer
    Dim arr As Variant
    Dim offset As Integer
    size = r1.Rows.Count * r2.Rows.Count
    ReDim arr(0 To size, 0 To 1)
    offset = 0

    For i = 1 To r1.Rows.Count
        For j = 1 To r2.Rows.Count
            arr(offset, 0) = r1.Cells(i, 1).Value2
            arr(offset, 1) = r2.Cells(j, 1).Value2
            offset = offset + 1
        Next j
    Next i

    CrossJoin = arr
End Function

To use the function select and empty cell and insert =CROSSJOIN(A1:A4, B1:B4) (adjusting the input range as required) then when the function has evaluated extend the range to the size of the expected cross join. (in this case 16x2).

To calculate the array function hit F2 then press Ctrl+Shift+Enter to calculate the array.