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

Some times there are not output from requests.
{
    NamesAndTypesList partition_key_columns;
    if (!partition_key.column_names.empty())
        partition_key_columns = partition_key.expression->getRequiredColumnsWithTypes();
    return std::make_shared<ExpressionActions>(std::make_shared<ActionsDAG>(partition_key_columns), settings);
}
Names MergeTreeData::getMinMaxColumnsNames(const KeyDescription & partition_key)
{
    if (!partition_key.column_names.empty())
        return partition_key.expression->getRequiredColumns();
    return {};
}
DataTypes MergeTreeData::getMinMaxColumnsTypes(const KeyDescription & partition_key)
{
    if (!partition_key.column_names.empty())
        return partition_key.expression->getRequiredColumnsWithTypes().getTypes();
    return {};
}
ExpressionActionsPtr MergeTreeData::getPrimaryKeyAndSkipIndicesExpression(const StorageMetadataPtr & metadata_snapshot) const