```
SELECT *
FROM system.dictionaries
WHERE name LIKE 'XXXX%'

Row 1:
──────
database:                    default
name:                        XXXX_dict
uuid:                        00000000-0000-0000-0000-000000000000
status:                      LOADED
origin:                      default.XXXX_dict
type:                        Polygon
key:                         (Array(Array(Array(Array(Float64)))))
attribute.names:             ['name','id']
attribute.types:             ['String','String']
bytes_allocated:             0
query_count:                 0
hit_rate:                    1
element_count:               433731
load_factor:                 1
source:                      ClickHouse: default.XXXX
lifetime_min:                60
lifetime_max:                1800
loading_start_time:          2021-03-11 00:07:52
last_successful_update_time: 2021-03-11 00:08:24
loading_duration:            31.595
last_exception:
```
kMinIntersections(min_intersections_), kMaxDepth(max_depth_), polygons(polygons_)
    {
        setBoundingBox();
        std::vector<size_t> order(polygons.size());
        std::iota(order.begin(), order.end(), 0);
        root = makeCell(min_x, min_y, max_x, max_y, order);
    }
    /** Retrieves the cell containing a given point.
      * A null pointer is returned when the point falls outside the grid.
      */
    [[nodiscard]] const ReturnCell * find(Coord x, Coord y) const override
    {
        if (x < min_x || x >= max_x)
            return nullptr;
        if (y < min_y || y >= max_y)
            return nullptr;
        return root->find((x - min_x) / (max_x - min_x), (y - min_y) / (max_y - min_y));
    }
    
    static constexpr size_t kMultiProcessingDepth = 2;
    
    static constexpr Coord kEps = 1e-4;
private:
    std::unique_ptr<ICell<ReturnCell>> root = nullptr;
    Coord min_x = 0, min_y = 0;
    Coord max_x = 0, max_y = 0;
    const size_t kMinIntersections;
    const size_t kMaxDepth;
    const std::vector<Polygon> & polygons;
    std::unique_ptr<ICell<ReturnCell>> makeCell(Coord current_min_x, Coord current_min_y, Coord current_max_x, Coord current_max_y, std::vector<size_t> possible_ids, size_t depth = 0)