[C++] Implement "value counts" kernels for tabulating value frequencies #17585
Description
This is related to "match", "isin", and "unique" since hashing is generally required
Reporter: Wes McKinney / @wesm
Assignee: Micah Kornfield / @emkornfield
PRs and other links:
Note: This issue was originally created as ARROW-1572. Please see the migration documentation for further details.