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https://issues.apache.org/jira/browse/ARROW-3144?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Rok Mihevc updated ARROW-3144:
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    External issue URL: https://github.com/apache/arrow/issues/19492

> [C++] Move "dictionary" member from DictionaryType to ArrayData to allow for 
> changing dictionaries between Array chunks
> -----------------------------------------------------------------------------------------------------------------------
>
>                 Key: ARROW-3144
>                 URL: https://issues.apache.org/jira/browse/ARROW-3144
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++
>            Reporter: Wes McKinney
>            Assignee: Wes McKinney
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 0.14.0
>
>          Time Spent: 12h 40m
>  Remaining Estimate: 0h
>
> There are a couple of inter-related issues:
> * Cases where a system might send the schema without the dictionaries, and 
> the user wishes to reason about the schema and its types without knowing the 
> dictionary values
> * Dictionaries that are changing, e.g. using delta dictionary messages
> {{arrow::DictionaryType}} has no "linkage" to any external object. I propose 
> adding a "LinkedDictionaryType" or something similar (purely a C++ 
> construct), which functionally would be a subclass of {{DictionaryType}}, 
> which would allow a type to be created which will obtain its dictionary later 
> through some kind of "Dictionary provider" interface. There is something 
> similar in Java already. This would allow a dictionary to evolve via delta 
> dictionaries, or for a dictionary to be retrieved later e.g. through an RPC 
> or IPC layer



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