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https://issues.apache.org/jira/browse/ARROW-14744?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17468181#comment-17468181
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Dewey Dunnington commented on ARROW-14744:
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At this point, you're the one who's looked into this the most, so I'd suggest
you give whichever one you think is best a shot! [~thisisnic] has spend the
most time here and may have a suggestion. Both solutions sound reasonable on
paper but I find that it isn't until things are implemented (at least
partially) that a clearest path emerges. Go for it! If you run into problems
getting an Arrow development setup feel free to post here and we'll see what we
can do.
> [R] open_dataset() error when `schema` argument supplied, but `column_names`
> not supplied to `CSVReadOptions`
> -------------------------------------------------------------------------------------------------------------
>
> Key: ARROW-14744
> URL: https://issues.apache.org/jira/browse/ARROW-14744
> Project: Apache Arrow
> Issue Type: Bug
> Components: R
> Reporter: Nicola Crane
> Priority: Major
> Fix For: 7.0.0
>
>
> Note: this occurs regardless of whether the data has a header or not
> {code:r}
> td <- tempfile()
> dir.create(td)
> readr::write_csv(ggplot2::diamonds, file=file.path(td, 'diamonds.csv'),
> col_names=FALSE)
> readLines(file.path(td, "diamonds.csv"), n = 2)
> open_dataset(
> td,
> format = 'csv',
> schema = diamond_schema,
> partitioning = NULL,
> skip_rows = 1,
> unify_schemas = FALSE,
> read_options = arrow::CsvReadOptions$create(
> skip_rows = 1,
> column_names = names(diamond_schema)
> )
> ) %>%
> collect()
> # # A tibble: 53,939 × 10
> # carat cut color clarity depth table price x y z
> # <dbl> <chr> <chr> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
> # 1 0.21 Premium E SI1 59.8 61 326 3.89 3.84 2.31
> # 2 0.23 Good E VS1 56.9 65 327 4.05 4.07 2.31
> # 3 0.29 Premium I VS2 62.4 58 334 4.2 4.23 2.63
> # 4 0.31 Good J SI2 63.3 58 335 4.34 4.35 2.75
> # 5 0.24 Very Good J VVS2 62.8 57 336 3.94 3.96 2.48
> # 6 0.24 Very Good I VVS1 62.3 57 336 3.95 3.98 2.47
> # 7 0.26 Very Good H SI1 61.9 55 337 4.07 4.11 2.53
> # 8 0.22 Fair E VS2 65.1 61 337 3.87 3.78 2.49
> # 9 0.23 Very Good H VS1 59.4 61 338 4 4.05 2.39
> # 10 0.3 Good J SI1 64 55 339 4.25 4.28 2.73
> # # … with 53,929 more rows
> open_dataset(
> td,
> format='csv',
> schema = diamond_schema,
> skip_rows = 1,
> read_options=arrow::CsvReadOptions$create(skip_rows=1)) %>%
> collect()
> # # A tibble: 53,938 × 10
> # carat cut color clarity depth table price x y z
> # <dbl> <chr> <chr> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
> # 1 NA NA NA NA NA NA NA NA NA NA
> # 2 NA NA NA NA NA NA NA NA NA NA
> # 3 NA NA NA NA NA NA NA NA NA NA
> # 4 NA NA NA NA NA NA NA NA NA NA
> # 5 NA NA NA NA NA NA NA NA NA NA
> # 6 NA NA NA NA NA NA NA NA NA NA
> # 7 NA NA NA NA NA NA NA NA NA NA
> # 8 NA NA NA NA NA NA NA NA NA NA
> # 9 NA NA NA NA NA NA NA NA NA NA
> # 10 NA NA NA NA NA NA NA NA NA NA
> # # … with 53,928 more rows
> {code}
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