gistfile1.txt

    meter_reading_db_df = pandas.read_sql(
        (
            """select t.meter_type, reading_time, usage from meter_reading a
            inner join meter m on (a.meter_id = m.meter_id)
            inner join meter_type t on (m.meter_type_id = t.meter_type_id)
            where meter_name in ( %(meter)s )
            and version_number in (select max(version_number)
            from meter_reading_version b
            where a.meter_id = b.meter_id)"""), 
        db_engine, 
        params={ "meter":meter }
    )