We have scalar aggregate kernels for these already that can serve as the basis for a hash aggregate implementation.

Depends on ARROW-12759 as that refactors  how hash aggregate kernels are implemented.

Reporter: David Li / @lidavidm
Assignee: David Li / @lidavidm

Related issues:

• [C++] Implement hash_aggregate kernels (umbrella issue) (is a child of)

PRs and other links:

• GitHub Pull Request #10792

_{Note: This issue was originally created as ARROW-13295. Please see the migration documentation for further details.}