Install a local copy of a taxadb snapshot

Downloads the Parquet files for the requested provider(s) into taxadb_dir(), so that subsequent queries read from local disk instead of streaming from remote storage.

Usage

td_download(
  provider = getOption("taxadb_default_provider", "itis"),
  schema = c("dwc", "common"),
  version = latest_version(),
  overwrite = FALSE,
  db = td_connect()
)

Arguments

provider

a character vector of provider(s) to download. See available_providers() for the providers published in a given version.

schema

One of "dwc" (for Darwin Core data) or "common" (for the Common names table.)

version

Which version of the taxadb provider database should we use? defaults to latest. See available_versions() for details.

overwrite

should we re-download files that are already present? Default FALSE.

db

a connection to the taxadb database. See details.

Value

the local paths of the downloaded files, invisibly.

Details

Streaming is fast enough for most interactive use and requires no setup, so a local copy is optional. Install one when you will make many queries against the same table, when you need to work offline, or when you want a snapshot pinned on disk for reproducibility.

Snapshots are large: the Darwin Core tables for col and gbif are each several hundred MB. Use available_providers() to see what is published, and delete a local copy with unlink(taxadb_dir(), recursive = TRUE).

Examples

if (FALSE) { # \dontrun{
## Install a local copy of ITIS. Writes to taxadb_dir() and downloads
#  tens of MB, so this is never run unattended.
td_download("itis")
} # }