```
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] [                                                                                                                                                                                                                                        <=>               ]
```

auto file_name = current_path.substr(last_slash_pos + 1);
            auto column = DataTypeString().createColumnConst(num_rows, std::move(file_name));
            columns.push_back(column->convertToFullColumnIfConst());
        }
        return Chunk(std::move(columns), num_rows);
    }
    {
        std::lock_guard lock(reader_mutex);
        reader.reset();
        pipeline.reset();
        read_buf.reset();
        if (!initialize())
            return {};
    }
    return generate();
}
class HDFSSink : public SinkToStorage
{
public:
    HDFSSink(const String & uri,
        const String & format,
        const Block & sample_block,
        ContextPtr context,
        const CompressionMethod compression_method)
        : SinkToStorage(sample_block)
    {
        write_buf = wrapWriteBufferWithCompressionMethod(std::make_unique<WriteBufferFromHDFS>(uri, context->getGlobalContext()->getConfigRef(), context->getSettingsRef().hdfs_replication), compression_method, 3);
        writer = FormatFactory::instance().getOutputFormatParallelIfPossible(format, *write_buf, sample_block, context);
    }
    String getName() const override { return "HDFSSink"; }