'Get a breakdown of top pages per interval, i.e.
day         url     count
2014-01-01  /blog/  11
2014-01-02  /blog/  14
2014-01-03  /blog/  9'

def top_pages_by_time_period(self, interval='day'):

    date_trunc = fn.date_trunc(interval, PageView.timestamp)
    return self.get_query().select(PageView.url, date_trunc.alias(interval), fn.Count(PageView.id).alias('count')).group_by(PageView.url, date_trunc).order_by(SQL(interval), SQL('count').desc(), PageView.url)
