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

Some times there are not output from requests.
{
    switch (type.getValue())
    {
        case MergeTreeDataPartType::Wide:
            ProfileEvents::increment(ProfileEvents::MergedIntoWideParts);
            break;
        case MergeTreeDataPartType::Compact:
            ProfileEvents::increment(ProfileEvents::MergedIntoCompactParts);
            break;
        case MergeTreeDataPartType::InMemory:
            ProfileEvents::increment(ProfileEvents::MergedIntoInMemoryParts);
            break;
        default:
            break;
    }
}
MergeTreeData::MutableDataPartPtr MergeTreeData::createEmptyPart(