```
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:
```
#pragma once
#include <atomic>
#include <variant>
#include <Core/Block.h>
#include <Columns/ColumnDecimal.h>
#include <Columns/ColumnString.h>
#include <Common/Arena.h>
#include <boost/geometry.hpp>
#include <boost/geometry/geometries/multi_polygon.hpp>
#include "DictionaryStructure.h"
#include "IDictionary.h"
#include "IDictionarySource.h"
#include "DictionaryHelpers.h"
namespace DB
{
namespace bg = boost::geometry;
/** An interface for polygon dictionaries.
  * Polygons are read and stored as multi_polygons from boost::geometry in Euclidean coordinates.
  * An implementation should inherit from this base class and preprocess the data upon construction if needed.
  * It must override the find method of this class which retrieves the polygon containing a single point.
  */
class IPolygonDictionary : public IDictionaryBase