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

if (auto meta = file_infos.meta_by_inode.find(inode);
                    meta != file_infos.meta_by_inode.end() && meta->second.file_name == file_name)
                    file_infos.meta_by_inode.erase(meta);
                if (std::filesystem::exists(getFullMetaPath(file_name)))
                    std::filesystem::remove(getFullMetaPath(file_name));
                file_infos.context_by_name.erase(it);
            }
            else
            {
                valid_files.push_back(file_name);
            }
        }
    }
    file_infos.file_names.swap(valid_files);
    
    assert(file_infos.file_names.size() == file_infos.meta_by_inode.size());
    assert(file_infos.file_names.size() == file_infos.context_by_name.size());
    return events.empty() || file_infos.file_names.empty();
}
NamesAndTypesList StorageFileLog::getVirtuals() const
{
    return NamesAndTypesList{{"_filename", std::make_shared<DataTypeString>()}, {"_offset", std::make_shared<DataTypeUInt64>()}};
}
Names StorageFileLog::getVirtualColumnNames()
{
    return {"_filename", "_offset"};
}
}