Comparison of Dictionary, Collections and Arrays

Question

I am trying to work out the relative benefits and features of dictionaries compared with collections and arrays.

I found an excellent article here but can\'t find a

Answer 1

Option Explicit

Sub UpdateSummary()

    Dim varData
    Dim objDicCountry As Object
    Dim objDicCity As Object
    Dim objDicData As Object
    Dim lngR As Long
    Dim varResult
    Dim lngC As Long
    Dim strKey As String
    Dim varUnique

    varData = Sheet12.Range("A1").CurrentRegion
    Set objDicCity = CreateObject("Scripting.Dictionary")
    Set objDicCountry = CreateObject("Scripting.Dictionary")
    Set objDicData = CreateObject("Scripting.Dictionary")

    For lngR = LBound(varData) + 1 To UBound(varData)

        strKey = varData(lngR, 1) '--Country
        objDicCountry.Item(strKey) = ""

        strKey = varData(lngR, 2) '--City
        objDicCity.Item(strKey) = ""

        strKey = varData(lngR, 1) & "|" & varData(lngR, 2) '--Country and City
        objDicData.Item(strKey) = objDicData.Item(strKey) + varData(lngR, 3)

    Next lngR

    ReDim varResult(1 To objDicCountry.Count + 1, 1 To objDicCity.Count + 1)

    varUnique = objDicCountry.keys '--get Unique Country

    For lngR = LBound(varUnique) To UBound(varUnique)
        varResult(lngR + 2, 1) = varUnique(lngR)
    Next lngR

    varUnique = objDicCity.keys '--get Unique City

    For lngC = LBound(varUnique) To UBound(varUnique)
        varResult(1, lngC + 2) = varUnique(lngC)
    Next lngC


    For lngR = LBound(varResult) + 1 To UBound(varResult)
        For lngC = LBound(varResult) + 1 To UBound(varResult, 2)
            strKey = varResult(lngR, 1) & "|" & varResult(1, lngC) '--Country & "|" & City
            varResult(lngR, lngC) = objDicData.Item(strKey)
        Next lngC
    Next lngR

    Sheet12.Range("F6").Resize(UBound(varResult), UBound(varResult, 2)).Value = varResult
    MsgBox "Done", vbInformation

End Sub