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https://issues.apache.org/jira/browse/ARROW-17313?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17576914#comment-17576914
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Antoine Pitrou commented on ARROW-17313:
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Well, if arbitrary byte ranges need to be supported, then some scanning will be
required when starting to read the CSV file. And we need to error out if
{{allow_newlines_in_values}} is true.
An additional complication: what happens with e.g. a {{.csv.gz}} file?
> [C++] Add Byte Range to CSV Reader ReadOptions
> ----------------------------------------------
>
> Key: ARROW-17313
> URL: https://issues.apache.org/jira/browse/ARROW-17313
> Project: Apache Arrow
> Issue Type: Improvement
> Components: C++, Python
> Reporter: Ziheng Wang
> Assignee: Ziheng Wang
> Priority: Major
>
> Sometimes it's desirable to just read a portion of a CSV. The best way to do
> that is to pass in a list of byte ranges to CSV read options that specify
> where in the CSV you want to read. These byte ranges don't necessarily have
> to be aligned on line break boundaries, the CSV reader should just read until
> the end of the line, and skip anything before the first line break in a byte
> range.
> Based on discussion, the scope is going to be reduced here. The first
> implementation will support a single byte range that is already assumed to be
> aligned on byte boundaries.
> Will not handle quotes/returns and other edge cases.
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