Statistics
https://play.clickhouse.com/play?user=play#c2VsZWN0IAp0b1N0YXJ0T2ZIb3VyKGNoZWNrX3N0YXJ0X3RpbWUpIGFzIGQsCmNvdW50KCksICBncm91cFVuaXFBcnJheShwdWxsX3JlcXVlc3RfbnVtYmVyKSwgIGFueShyZXBvcnRfdXJsKQpmcm9tIGNoZWNrcyB3aGVyZSAnMjAyMi0wNi0wMScgPD0gY2hlY2tfc3RhcnRfdGltZSBhbmQgdGVzdF9uYW1lIGxpa2UgJyUwMjQ5MV9wYXJ0X2xvZ19oYXNfdGFibGVfdXVpZCUnIGFuZCB0ZXN0X3N0YXR1cyBpbiAoJ0ZBSUwnLCAnRkxBS1knKSBncm91cCBieSBkIG9yZGVyIGJ5IGQgZGVzYw==

Some times there are not output from requests.
boost::iterator_range<DataPartIteratorByStateAndInfo> range, const ColumnsDescription & storage_columns)
{
    return DB::getConcreteObjectColumns(
        range.begin(), range.end(),
        storage_columns, [](const auto & part) -> const auto & { return part->getColumns(); });
}
void MergeTreeData::resetObjectColumnsFromActiveParts(const DataPartsLock & )
{
    auto metadata_snapshot = getInMemoryMetadataPtr();
    const auto & columns = metadata_snapshot->getColumns();
    if (!hasDynamicSubcolumns(columns))
        return;
    auto range = getDataPartsStateRange(DataPartState::Active);
    object_columns = getConcreteObjectColumns(range, columns);
}
void MergeTreeData::updateObjectColumns(const DataPartPtr & part, const DataPartsLock & )
{
    auto metadata_snapshot = getInMemoryMetadataPtr();
    const auto & columns = metadata_snapshot->getColumns();
    if (!hasDynamicSubcolumns(columns))
        return;
    DB::updateObjectColumns(object_columns, columns, part->getColumns());
}
StorageSnapshotPtr MergeTreeData::getStorageSnapshot(const StorageMetadataPtr & metadata_snapshot, ContextPtr query_context) const