[ARROW-15540] [C++] Allow the substrait consumer to accept plans with hints and nullable literals

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 10.0.0
• Component/s: C++
• Labels: pull-request-available substrait
• External issue URL: https://github.com/apache/arrow/issues/31011
• Assignee: Unassigned
• Reporter: Weston Pace
• Created: 03/Feb/22 04:19
• Updated: 11/Jan/23 11:37
• Resolved: 15/Oct/22 18:21

Description

The first pass of the substrait consumer was created with the philosophy of rejecting any plan that it could not safely round trip (e.g. Substrait -> Arrow Exec Plan -> Substrait).

As a result it rejects plans that contain elements we cannot represent in Arrow Exec Plans. Two prominent elements that are likely to start existing soon in producers are nullable literals and hints.

To put it another way, a producer might insert a hint like "this column is sorted" into a plan. Currently the Arrow exec plans can't make use of this kind of data. So rather than just ignore the hint we reject the plan.

Issue Links

• depends upon: ARROW-16988 [C++] Introduce Substrait ToProto/FromProto conversion options
• links to: GitHub Pull Request #14402