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40 | Configuring an External Dictionary |
Configuring an External Dictionary
If dictionary is configured using xml file, than dictionary configuration has the following structure:
<dictionary>
<name>dict_name</name>
<structure>
<!-- Complex key configuration -->
</structure>
<source>
<!-- Source configuration -->
</source>
<layout>
<!-- Memory layout configuration -->
</layout>
<lifetime>
<!-- Lifetime of dictionary in memory -->
</lifetime>
</dictionary>
Corresponding DDL-query has the following structure:
CREATE DICTIONARY dict_name
(
... -- attributes
)
PRIMARY KEY ... -- complex or single key configuration
SOURCE(...) -- Source configuration
LAYOUT(...) -- Memory layout configuration
LIFETIME(...) -- Lifetime of dictionary in memory
name
– The identifier that can be used to access the dictionary. Use the characters[a-zA-Z0-9_\-]
.- source — Source of the dictionary.
- layout — Dictionary layout in memory.
- structure — Structure of the dictionary . A key and attributes that can be retrieved by this key.
- lifetime — Frequency of dictionary updates.