[ARROW-15854] [C++] Refine csv writer - populate columns in normal order

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 8.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/31291
• Assignee: Yibo Cai
• Reporter: Yibo Cai
• Created: 05/Mar/22 13:42
• Updated: 11/Jan/23 11:40
• Resolved: 09/Mar/22 00:54

Description

CSV writer populates columns in reverse order, each row is constructed from last cell to first cell.
Populating columns in normal order makes the code easier to follow, and offers better optimization chances. E.g., EscapeReverse [1] is the hotspot for quoted string benchmark, it's hard to improve if chars are scanned in reverse order, but may benefit from simd if scanned in normal order.

[1] https://github.com/apache/arrow/blob/master/cpp/src/arrow/csv/writer.cc#L141-L150

Issue Links

• links to: GitHub Pull Request #12574