This query does not show realtime metrics:

```
INSERT INTO wikistat 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,
    CAST(values[3], 'UInt64') AS hits
FROM s3('https://....s3.eu-central-1.amazonaws.com/wikistat/original/*.gz', '...', '...', LineAsString, auto)
WHERE length(values) >= 3
```

Although this query does:

```
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,
    CAST(values[3], 'UInt64') AS hits
FROM s3('https://....s3.eu-central-1.amazonaws.com/wikistat/original/*.gz', '...', '...', LineAsString, auto)
WHERE length(values) >= 3
```

I also was not able to cancel the first query.
{
        std::lock_guard lock(mutex);
        if (uris_iter == uris.end())
            return "";
        auto key = *uris_iter;
        ++uris_iter;
        return key;
    }
private:
    std::mutex mutex;
    Strings uris;
    Strings::iterator uris_iter;
};
Block HDFSSource::getHeader(const StorageMetadataPtr & metadata_snapshot, bool need_path_column, bool need_file_column)
{
    auto header = metadata_snapshot->getSampleBlock();
    
    if (need_path_column)
        header.insert(
            {DataTypeLowCardinality{std::make_shared<DataTypeString>()}.createColumn(),
             std::make_shared<DataTypeLowCardinality>(std::make_shared<DataTypeString>()),
             "_path"});
    if (need_file_column)
        header.insert(
            {DataTypeLowCardinality{std::make_shared<DataTypeString>()}.createColumn(),
             std::make_shared<DataTypeLowCardinality>(std::make_shared<DataTypeString>()),
             "_file"});
    return header;
}
Block HDFSSource::getBlockForSource(