[jira] [Commented] (ARROW-10219) [C++] csv::TableReader column names, Read() arguments

["Antoine Pitrou (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/ARROW-10219?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17209724#comment-17209724 ] 

Antoine Pitrou commented on ARROW-10219:
----------------------------------------

I'm not sure I understand #1, can you explain a bit more?
As for #2, by giving {{ConvertOptions::include_columns}} you can already restrict which columns you want to convert.

> [C++] csv::TableReader column names, Read() arguments
> -----------------------------------------------------
>
>                 Key: ARROW-10219
>                 URL: https://issues.apache.org/jira/browse/ARROW-10219
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++
>            Reporter: Neal Richardson
>            Priority: Major
>             Fix For: 3.0.0
>
>
> Some feature requests:
> * csv::TableReader {{column_names}} method, and/or {{schema}} method. This will (in most cases) require IO to get these from the file, but that's fine. There are use cases (we've seen in R) where it would help to be able to get the names from the file (e.g. when you specify column types, it's a map of column name to type, so you can't currently specify types without also specifying names)
> * Add Read(std::vector<int>) like how feather (and parquet?) have so that you don't have to parse and allocate columns you don't want.
> cc [~apitrou] [~romainfrancois]



--
This message was sent by Atlassian Jira
(v8.3.4#803005)