targets: tar_resources_parquet – R documentation

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tar_resources_parquet

Target resources: parquet storage formats

Description

Create the parquet argument of tar_resources()`` to specify optional settings for parquet data frame storage formats powered by the arrowR package. See theformat' argument of tar_target() for details.

Usage

tar_resources_parquet(compression = "snappy", compression_level = NULL)

Arguments

`compression`	Character of length 1, `compression` argument of `arrow::write_parquet()`.
`compression_level`	Numeric of length 1, `compression_level` argument of `arrow::write_parquet()`.

Value

Object of class "tar_resources_parquet", to be supplied to the parquet argument of tar_resources().

Resources

Functions tar_target() and tar_option_set() each takes an optional resources argument to supply non-default settings of various optional backends for data storage and high-performance computing. The tar_resources() function is a helper to supply those settings in the correct manner. Resources are all-or-nothing: if you specify any resources with tar_target(), all the resources from tar_option_get("resources") are dropped for that target. In other words, if you write tar_option_set(resources = resources_1) and then tar_target(x, my_command(), resources = resources_2), then everything in resources_1 is discarded for target x.

Examples

# Somewhere in you target script file (usually _targets.R):
tar_target(
  name,
  command(),
  format = "parquet",
  resources = tar_resources(
    parquet = tar_resources_parquet(compression = "lz4")
  )
)

targets

Dynamic Function-Oriented 'Make'-Like Declarative Workflows

v0.10.0

MIT + file LICENSE

Authors

William Michael Landau [aut, cre] (<https://orcid.org/0000-0003-1878-3253>), Matthew T. Warkentin [ctb], Samantha Oliver [rev] (<https://orcid.org/0000-0001-5668-1165>), Tristan Mahr [rev] (<https://orcid.org/0000-0002-8890-5116>), Eli Lilly and Company [cph]

Initial release