add_filename {arrow} | R Documentation |
This function only exists inside arrow
dplyr
queries, and it only is
valid when quering on a FileSystemDataset
.
add_filename()
To use filenames generated by this function in subsequent pipeline steps, you
must either call compute()
or
collect()
first. See Examples.
A FieldRef
Expression
that refers to the filename
augmented column.
## 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)