[ARROW-13498] [C++] ScanNode takes filter but doesn't filter

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Component/s: C++
• Labels: query-engine
• External issue URL: https://github.com/apache/arrow/issues/29157
• Assignee: Unassigned
• Reporter: Neal Richardson
• Created: 29/Jul/21 19:57
• Updated: 11/Jan/23 08:33
• Resolved: 16/Sep/21 16:45

Description

This turned out to be my confusion in ARROW-13344: because the ScanNode takes a filter and projection, I wasn't creating a FilterNode because I assume that the filter is already applied--why else would I provide a filter to the ScanNode? But it turns out that if you don't Filter again, you get unfiltered results:

Table$create(
  group=c(1, 2), 
  value=c(5, 6)
) %>% 
  filter(value > 5) %>% 
  group_by(group) %>% 
  summarize(sum(value)) %>% 
  collect()

# A tibble: 2 x 2
  group `sum(value)`
  <dbl>        <dbl>
1     1            5
2     2            6

Issue Links

• is duplicated by: ARROW-14642 [C++] ScanNode is not using the filter expression
• relates to: ARROW-13344 [R] Initial bindings for ExecPlan/ExecNode