ClickHouse/docs/fr/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-hierarchical.md
Ivan Blinkov cd14f9ebcb
SQL reference refactoring (#10857)
* split up select.md

* array-join.md basic refactoring

* distinct.md basic refactoring

* format.md basic refactoring

* from.md basic refactoring

* group-by.md basic refactoring

* having.md basic refactoring

* additional index.md refactoring

* into-outfile.md basic refactoring

* join.md basic refactoring

* limit.md basic refactoring

* limit-by.md basic refactoring

* order-by.md basic refactoring

* prewhere.md basic refactoring

* adjust operators/index.md links

* adjust sample.md links

* adjust more links

* adjust operatots links

* fix some links

* adjust aggregate function article titles

* basic refactor of remaining select clauses

* absolute paths in make_links.sh

* run make_links.sh

* remove old select.md locations

* translate docs/es

* translate docs/fr

* translate docs/fa

* remove old operators.md location

* change operators.md links

* adjust links in docs/es

* adjust links in docs/es

* minor texts adjustments

* wip

* update machine translations to use new links

* fix changelog

* es build fixes

* get rid of some select.md links

* temporary adjust ru links

* temporary adjust more ru links

* improve curly brace handling

* adjust ru as well

* fa build fix

* ru link fixes

* zh link fixes

* temporary disable part of anchor checks
2020-05-15 07:34:54 +03:00

71 lines
2.2 KiB
Markdown

---
machine_translated: true
machine_translated_rev: 72537a2d527c63c07aa5d2361a8829f3895cf2bd
toc_priority: 45
toc_title: "Dictionnaires hi\xE9rarchiques"
---
# Dictionnaires Hiérarchiques {#hierarchical-dictionaries}
Clickhouse prend en charge les dictionnaires hiérarchiques avec un [touche numérique](external-dicts-dict-structure.md#ext_dict-numeric-key).
Voici une structure hiérarchique:
``` text
0 (Common parent)
├── 1 (Russia)
│ │
│ └── 2 (Moscow)
│ │
│ └── 3 (Center)
└── 4 (Great Britain)
└── 5 (London)
```
Cette hiérarchie peut être exprimée comme la table de dictionnaire suivante.
| id\_région | région\_parent | nom\_région |
|------------|----------------|--------------------|
| 1 | 0 | Russie |
| 2 | 1 | Moscou |
| 3 | 2 | Center |
| 4 | 0 | La Grande-Bretagne |
| 5 | 4 | Londres |
Ce tableau contient une colonne `parent_region` qui contient la clé du parent le plus proche de l'élément.
Clickhouse soutient le [hiérarchique](external-dicts-dict-structure.md#hierarchical-dict-attr) propriété pour [externe dictionnaire](index.md) attribut. Cette propriété vous permet de configurer le dictionnaire hiérarchique comme décrit ci-dessus.
Le [dictGetHierarchy](../../../sql-reference/functions/ext-dict-functions.md#dictgethierarchy) la fonction vous permet d'obtenir la chaîne parent d'un élément.
Pour notre exemple, la structure du dictionnaire peut être la suivante:
``` xml
<dictionary>
<structure>
<id>
<name>region_id</name>
</id>
<attribute>
<name>parent_region</name>
<type>UInt64</type>
<null_value>0</null_value>
<hierarchical>true</hierarchical>
</attribute>
<attribute>
<name>region_name</name>
<type>String</type>
<null_value></null_value>
</attribute>
</structure>
</dictionary>
```
[Article Original](https://clickhouse.tech/docs/en/query_language/dicts/external_dicts_dict_hierarchical/) <!--hide-->