```
ubuntu@ip-172-31-79-147:/opt/downloads$ clickhouse-local --max_threads 8 --query "WITH parseDateTimeBestEffort(extract(_path, 'pageviews-([\\d\\-]+)\\.gz$')) AS time, splitByChar(' ', line) AS values, splitByChar('.', values[1]) AS projects SELECT time, projects[1] AS project, projects[2] AS subproject, values[2] AS path, (values[3])::UInt64 AS hits FROM file('pageviews*.gz', LineAsString) WHERE length(values) >= 3" | pv > /dev/null
^C01GiB 0:01:08 [ 129MiB/s] [                                                                                                                                                                   <=>                                                                                    ]

ubuntu@ip-172-31-79-147:/opt/downloads$ clickhouse-local --max_threads 8 --query "WITH parseDateTimeBestEffort(extract(toLowCardinality(_path), 'pageviews-([\\d\\-]+)\\.gz$')) AS time, splitByChar(' ', line) AS values, splitByChar('.', values[1]) AS projects SELECT time, projects[1] AS project, projects[2] AS subproject, values[2] AS path, (values[3])::UInt64 AS hits FROM file('pageviews*.gz', LineAsString) WHERE length(values) >= 3" | pv > /dev/null
^C46GiB 0:00:48 [ 175MiB/s] [                                                                                                                                                                                                                                        <=>               ]
```

iterator_wrapper = std::make_shared<HDFSSource::IteratorWrapper>([uris_iterator]()
        {
            return uris_iterator->next();
        });
    }
    Pipes pipes;
    auto this_ptr = std::static_pointer_cast<StorageHDFS>(shared_from_this());
    for (size_t i = 0; i < num_streams; ++i)
    {
         const auto get_columns_for_format = [&]() -> ColumnsDescription
        {
            if (isColumnOriented())
                return ColumnsDescription{
                    metadata_snapshot->getSampleBlockForColumns(column_names, getVirtuals(), getStorageID()).getNamesAndTypesList()};
            else
                return metadata_snapshot->getColumns();
        };
        pipes.emplace_back(std::make_shared<HDFSSource>(
            this_ptr,
            metadata_snapshot,
            context_,
            max_block_size,
            need_path_column,
            need_file_column,
            iterator_wrapper,
            get_columns_for_format()));
    }
    return Pipe::unitePipes(std::move(pipes));
}
SinkToStoragePtr StorageHDFS::write(const ASTPtr & query, const StorageMetadataPtr & metadata_snapshot, ContextPtr context_)