def datetime_extract_sql(self, lookup_type, field_name, tzname):
        raise NotImplementedError()
Given a lookup_type of 'year', 'month', 'day', 'hour', 'minute' or
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/Django-1.6.10/django/db/backends/__init__.py/BaseDatabaseOperations.datetime_extract_sql