def METHOD_NAME(ferc_to_sqlite_settings, pudl_datastore_fixture, extractor_class):
    """Check to make sure we aren't missing any old FERC Form N tables or fields.
    Exhaustively enumerate all historical sets of FERC Form N database tables and their
    constituent fields. Check to make sure that the current database definition, based
    on the given reference year and our compilation of the DBF filename to table name
    mapping from 2015, includes every single table and field that appears in the
    historical FERC Form 1 data.
    """
    dataset = extractor_class.DATASET
    dbf_settings = getattr(ferc_to_sqlite_settings, f"{dataset}_dbf_to_sqlite_settings")
    refyear = dbf_settings.refyear
    dbf_reader = FercDbfReader(pudl_datastore_fixture, dataset=dataset)
    ref_archive = dbf_reader.get_archive(year=refyear, data_format="dbf")
    logger.info(f"Checking for new, unrecognized {dataset} tables in {refyear}.")
    table_schemas = ref_archive.get_db_schema()
    for table in table_schemas:
        if table not in dbf_reader.get_table_names():
            raise AssertionError(
                f"New {dataset} table '{table}' in {refyear} "
                f"does not exist in canonical list of tables"
            )
    # Retrieve all supported partitions for the dataset
    descriptor = pudl_datastore_fixture.get_datapackage_descriptor(dataset)
    parts = list(descriptor.get_partition_filters(data_format="dbf"))
    for yr in dbf_settings.years:
        # Check that for each year in the settings, there are partitions defined.
        yr_parts = [p for p in parts if p.get("year", None) == yr]
        if not yr_parts:
            logger.debug(f"Partitions supported by {dataset} are: {parts}")
            raise AssertionError(f"No partitions found for {dataset} in year {yr}.")
        # Check that validation function picks exactly one partition for each year.
        yr_valid_parts = [p for p in yr_parts if extractor_class.is_valid_partition(p)]
        if len(yr_valid_parts) != 1:
            logger.debug(
                f"Filter for {dataset} for year {yr} is: {yr_valid_parts} "
                f"(from {yr_parts})"
            )
            raise AssertionError(
                f"is_valid_partition() function for {dataset} "
                f"should select exactly one partition for year {yr}."
            )
        logger.info(f"Searching for lost {dataset} tables and fields in {yr}.")
        yr_archive = dbf_reader.get_archive(**yr_valid_parts[0])
        for table in yr_archive.get_db_schema():
            if table not in dbf_reader.get_table_names():
                raise AssertionError(
                    f"Long lost FERC1 table: '{table}' found in year {yr}. "
                    f"Refyear: {refyear}"
                )
            # Check that legacy fields have not been lost (i.e. they're present in refyear)
            yr_columns = yr_archive.get_table_schema(table).get_column_names()
            ref_columns = ref_archive.get_table_schema(table).get_column_names()
            unknowns = yr_columns.difference(ref_columns)
            if unknowns:
                raise AssertionError(
                    f"Long lost FERC1 fields '{sorted(unknowns)}' found in table "
                    f"'{table}' from year {yr}. "
                    f"Refyear: {refyear}"
                )