[ARROW-15441] [C++][Compute] hash_count aggregation of a null type column is incorrect

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 7.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/30921
• Assignee: Chenxi Li
• Reporter: Chenxi Li
• Created: 25/Jan/22 07:33
• Updated: 11/Jan/23 11:37
• Resolved: 26/Jan/22 19:18

Description

The result of hash_count such array is incorrect.

argument	key
NULL	1
NULL	1

 

CountOptions	Expected	Actual
ALL	2	2
ONLY_VALID	0	2
ONLY_NULL	2	0

Issue Links

• links to: GitHub Pull Request #12251