Function findIn2DimArr(data, arrName, arrField, arrUBound)
    Dim i As Long

    findIn2DimArr = False

    'Data getting
    For i = 0 To CLng(arrUBound)

        If arrName(i, arrField) = data Then
        
            findIn2DimArr = True
            Exit Function
            
        End If
        
    Next i

End Function

Sub Test()

    ReDim myArr(1000000, 4)
    ReDim firstSomeArr(1000000, 4)
    ReDim secondSomeArr(1000000, 4)
    
    ReDim oneDimensionalArr(1000000)

    For i = 0 To arrUBound
    
        'If base wasn't added earlier - add to
        If findIn2DimArr(myArr(i, 2), firstSomeArr, 2, firstSomeUBound) = True And findIn2DimArr(vbomArr(i, 2), secondSomeArr, 2, secondSomeUBound) = True Then
        
            'Add to one-dimensional array
            
            
        End If
            
    Next i

End Sub