add_filename function

Add the data filename as a column

This function only exists inside arrow dplyr queries, and it only is valid when querying on a FileSystemDataset.

add_filename()

Returns

A FieldRef Expression that refers to the filename augmented column.

Details

To use filenames generated by this function in subsequent pipeline steps, you must either call compute() or collect() first. See Examples.

Examples

## Not run:

open_dataset("nyc-taxi") %>% mutate(
  file =
    add_filename()
)

# To use a verb like mutate() with add_filename() we need to first call
# compute()
open_dataset("nyc-taxi") %>%
  mutate(file = add_filename()) %>%
  compute() %>%
  mutate(filename_length = nchar(file))
## End(Not run)