[ARROW-9609] [C++] CSV datasets don't materialize virtual columns

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.0.1, 2.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/25671
• Assignee: Ben Kietzman
• Reporter: Neal Richardson
• Created: 31/Jul/20 15:22
• Updated: 11/Jan/23 08:07
• Resolved: 04/Aug/20 16:21

Description

They're included but the values are all null.

Minimal reproducer in R:

library(arrow)
dir.create("testds/c=5", recursive = TRUE)
cat("a,b\n1,2\n", file = "testds/c=5/test.csv")
ds <- open_dataset("testds", format = "csv")
ds
## FileSystemDataset with 1 csv file
## a: int64
## b: int64
## c: int32
dplyr::collect(ds)
## # A tibble: 1 x 3
##       a     b     c
##   <int> <int> <int>
## 1     1     2    NA

 

Issue Links

• links to: GitHub Pull Request #7896