[ARROW-13501] [R] Bindings for count aggregation

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 6.0.0
• Component/s: R
• Labels: pull-request-available query-engine
• External issue URL: https://github.com/apache/arrow/issues/29159
• Assignee: Neal Richardson
• Reporter: Neal Richardson
• Created: 29/Jul/21 23:54
• Updated: 11/Jan/23 08:33
• Resolved: 30/Aug/21 17:59

Description

Not sure about the API on this because from what I understand from bkietz, every aggregation function takes a single field ref, but group_by then count doesn't require a field because you're counting how many rows are in each group. (Perhaps more importantly, dplyr::n() takes no arguments, so we don't have a field ref in our expression to start.)

Issue Links

• blocks: ARROW-13618 [R] Use Arrow engine for summarize() by default
• blocks: ARROW-13739 [R] Support dplyr::count() and tally()
• is blocked by: ARROW-13737 [C++] Support scalar columns in hash aggregations (was: hash_sum on scalar column segfaults)
• is related to: ARROW-13820 [R] Rename na.min_count to min_count and na.rm to skip_nulls
• relates to: ARROW-13344 [R] Initial bindings for ExecPlan/ExecNode
• relates to: ARROW-13620 [R] Binding for n_distinct()
• links to: GitHub Pull Request #10989