def upgrade():

    # main vars
    total_views = dict()
    file_handler = Path("migrations", "csv", "20140101-20141218_google_analytics.csv")

    # load csv data
    for path, views in reader(open(file_handler, "r")):

        # get whisky id from database
        if "/w/" in path:
            whisky_id = int(path.replace("/w/", ""))
            whisky = Whisky.query.get(whisky_id)
        else:
            whisky_slug = path.replace("/", "")
            new_whisky = Whisky(distillery=whisky_slug)
            new_slug = new_whisky.get_slug()
            whisky = Whisky.query.filter(Whisky.slug == new_slug).first()

        # feed temporary dictionary
        if whisky is not None:
            total_views[whisky.id] = total_views.get(whisky.id, 0) + int(views)

    # update db
    for whisky_id in total_views.keys():
        new_whisky = Whisky.query.get(whisky_id)
        new_whisky.views = total_views[whisky_id]
        db.session.add(new_whisky)

    # commit
    db.session.commit()