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https://issues.apache.org/jira/browse/ARROW-5811?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16887166#comment-16887166
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Wes McKinney commented on ARROW-5811:
-------------------------------------

I think we need to create an abstract C++ type (or similar) that is a 
{{ConversionRule}}. We have other types of conversion rules where we have not 
defined an API yet, for example "timestamp with striptime-like format of 
$FORMAT". Whatever API we have, it needs to be extensible to accommodate new 
kinds of logic

> [C++] CSV reader: Ability to not infer column types.
> ----------------------------------------------------
>
>                 Key: ARROW-5811
>                 URL: https://issues.apache.org/jira/browse/ARROW-5811
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++, Python
>    Affects Versions: 0.13.0
>         Environment: Ubuntu Xenial
>            Reporter: Bogdan Klichuk
>            Priority: Minor
>              Labels: csv, csvparser, pyarrow
>             Fix For: 1.0.0
>
>
> I'm trying to read CSV as is. All columns as strings. I don't know the schema 
> of these CSVs and they will vary as they are provided by user.
> Right now i'm using pandas.read_csv(dtype=str) which works great, but since 
> final destination of these CSVs are parquet files it seems like much more 
> efficient to use pyarrow.csv.read_csv in future, as soon as this becomes 
> available :)
> I tried things like 
> `pyarrow.csv.read_csv(convert_types=ConvertOptions(columns_types=defaultdict(lambda:
>  'string')))` but it doesn't work.
> Maybe I just didnt' find something that already exists? :)



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