'Parquet' is a columnar storage file format. This function enables you to read Parquet files into R.
read_parquet(
file,
col_select = NULL,
as_data_frame = TRUE,
props = ParquetArrowReaderProperties$create(),
...
)
A character file name or URI, raw
vector, an Arrow input stream,
or a FileSystem
with path (SubTreeFileSystem
).
If a file name or URI, an Arrow InputStream will be opened and
closed when finished. If an input stream is provided, it will be left
open.
A character vector of column names to keep, as in the
"select" argument to data.table::fread()
, or a
tidy selection specification
of columns, as used in dplyr::select()
.
Should the function return a data.frame
(default) or
an Arrow Table?
Additional arguments passed to ParquetFileReader$create()
A arrow::Table, or a data.frame
if as_data_frame
is
TRUE
(the default).
tf <- tempfile()
on.exit(unlink(tf))
write_parquet(mtcars, tf)
df <- read_parquet(tf, col_select = starts_with("d"))
head(df)
#> disp drat
#> 1 160 3.90
#> 2 160 3.90
#> 3 108 3.85
#> 4 258 3.08
#> 5 360 3.15
#> 6 225 2.76