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

Some times there are not output from requests.
{
    LOG_TRACE(log, "dropIfEmpty");
    auto lock = lockParts();
    if (!data_parts_by_info.empty())
        return;
    try
    {
        for (const auto & disk : getDisks())
        {
            if (disk->isBroken())
                continue;
            
            disk->removeFileIfExists(fs::path(relative_data_path) / MergeTreeData::FORMAT_VERSION_FILE_NAME);
            disk->removeDirectory(fs::path(relative_data_path) / MergeTreeData::DETACHED_DIR_NAME);
            disk->removeDirectory(relative_data_path);
        }
    }
    catch (...)
    {
        
        tryLogCurrentException(__PRETTY_FUNCTION__);
    }
}
namespace
{
bool isSafeForKeyConversion(const IDataType * from, const IDataType * to)