```
milovidov-desktop :) CREATE TABLE perf_lc_num(　        num UInt8,　        arr Array(LowCardinality(Int64)) default [num]　        ) ENGINE = TinyLog

CREATE TABLE perf_lc_num
(
    `num` UInt8,
    `arr` Array(LowCardinality(Int64)) DEFAULT [num]
)
ENGINE = TinyLog

Query id: e95f9a71-5795-4dea-8d80-4729fc8016b9

Ok.

0 rows in set. Elapsed: 0.002 sec. 

milovidov-desktop :) INSERT INTO perf_lc_num (num)
:-]         SELECT toUInt8(number)
:-]         FROM numbers(100000000)

INSERT INTO perf_lc_num (num) SELECT toUInt8(number)
FROM numbers(100000000)

Query id: 1101fd75-a545-4809-acb5-8afa2fae80c0


Received exception from server (version 20.13.1):
Code: 49. DB::Exception: Received from localhost:9000. DB::Exception: Got empty stream for DataTypeLowCardinality keys.: While executing SinkToOutputStream. 

0 rows in set. Elapsed: 0.045 sec. 

milovidov-desktop :) INSERT INTO perf_lc_num (num)　        SELECT toUInt8(number)　        FROM numbers(100000000)

INSERT INTO perf_lc_num (num) SELECT toUInt8(number)
FROM numbers(100000000)

Query id: 0ad8532a-5c6e-4590-84cd-7e00759d152d


Received exception from server (version 20.13.1):
Code: 49. DB::Exception: Received from localhost:9000. DB::Exception: Got empty stream for DataTypeLowCardinality keys.: While executing SinkToOutputStream. 

0 rows in set. Elapsed: 0.033 sec.
```

if (it != serialize_states.end())
        {
            settings.getter = createStreamGetter(column.name, written_streams);
            column.type->serializeBinaryBulkStateSuffix(settings, it->second);
        }
    }
    
    for (auto & stream : streams)
        stream.second->finalize();
    Strings column_files;
    for (auto & pair : streams)
        column_files.push_back(storage.files[pair.first].data_file_path);
    streams.clear();
    done = true;
    for (const auto & file : column_files)
        storage.file_checker.update(file);
    storage.file_checker.save();
}
void TinyLogBlockOutputStream::write(const Block & block)
{
    metadata_snapshot->check(block, true);
    
    WrittenStreams written_streams;
    for (size_t i = 0; i < block.columns(); ++i)
    {
        const ColumnWithTypeAndName & column = block.safeGetByPosition(i);
        writeData(column.name, *column.type, *column.column, written_streams);
    }
}
StorageTinyLog::StorageTinyLog(