[PARQUET-1993] [C++] Expose when prefetching completes

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: cpp-4.0.0
• Component/s: parquet-cpp
• Labels: pull-request-available
• Assignee: David Li
• Reporter: David Li
• Created: 01/Mar/21 22:23
• Updated: 10/Mar/21 14:13
• Resolved: 10/Mar/21 14:13

Description

As a follow up to PARQUET-1820, we should let an application be notified when pre-buffering has completed (e.g. PreBuffer() should return Future<void>). This would let an application pre-buffer some amount of data (across multiple files and/or row groups) and then decode data as it becomes available instead of blocking.

A more ergonomic API would be to expose Future<RecordBatchReader> or something along those lines.

Issue Links

• Is contained by: ARROW-11770 [C++] Add asynchronous read to readers
• links to: GitHub Pull Request #9613