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51 lines
1.6 KiB
Markdown
51 lines
1.6 KiB
Markdown
---
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toc_priority: 40
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toc_title: Configuring an External Dictionary
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---
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# Configuring an External Dictionary {#dicts-external-dicts-dict}
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If dictionary is configured using xml file, than dictionary configuration has the following structure:
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``` xml
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<dictionary>
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<name>dict_name</name>
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<structure>
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<!-- Complex key configuration -->
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</structure>
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<source>
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<!-- Source configuration -->
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</source>
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<layout>
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<!-- Memory layout configuration -->
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</layout>
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<lifetime>
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<!-- Lifetime of dictionary in memory -->
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</lifetime>
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</dictionary>
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```
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Corresponding [DDL-query](../../../sql-reference/statements/create/dictionary.md) has the following structure:
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``` sql
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CREATE DICTIONARY dict_name
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(
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... -- attributes
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)
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PRIMARY KEY ... -- complex or single key configuration
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SOURCE(...) -- Source configuration
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LAYOUT(...) -- Memory layout configuration
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LIFETIME(...) -- Lifetime of dictionary in memory
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```
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- `name` – The identifier that can be used to access the dictionary. Use the characters `[a-zA-Z0-9_\-]`.
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- [source](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md) — Source of the dictionary.
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- [layout](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-layout.md) — Dictionary layout in memory.
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- [structure](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-structure.md) — Structure of the dictionary . A key and attributes that can be retrieved by this key.
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- [lifetime](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md) — Frequency of dictionary updates.
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