R¶
Connect to CrateDB from R applications and notebooks.
About
The RPostgres package is the canonical C++ Interface to PostgreSQL, which is actively maintained and often preferred. An alternative is the RPostgreSQL package, written in C.
Synopsis
example.r
# Connect to CrateDB from R, using the "RPostgres: C++ Interface to PostgreSQL".
# https://cran.r-project.org/web/packages/RPostgres/
# Install the Postgres library on demand.
if (!requireNamespace("RPostgres", quietly = TRUE)) {
install.packages("RPostgres", repos="https://cran.r-project.org")
}
# Load the DBI and Postgres libraries.
library(DBI)
library(RPostgres)
# Connect to database.
conn <- dbConnect(RPostgres::Postgres(),
host = "localhost",
port = 5432,
sslmode = "disable",
user = "crate",
password = "crate",
)
on.exit(DBI::dbDisconnect(conn), add = TRUE)
# Invoke a basic select query.
res <- dbGetQuery(conn, "SELECT * FROM sys.summits ORDER BY height DESC LIMIT 10;")
print(res)
SSL connection
Use the sslmode = "require" parameter, and replace username, password,
and hostname with values matching your environment.
Also use this variant to connect to CrateDB Cloud.
conn <- dbConnect(RPostgres::Postgres(),
host = "testcluster.cratedb.net",
port = 5432,
sslmode = "require",
user = "admin",
password = "password",
)
Quickstart example
Create the file example.r including the synopsis code shared above.
Start CrateDB using Docker or Podman, then invoke the example program.
docker run --rm --publish=5432:5432 docker.io/crate '-Cdiscovery.type=single-node'
Rscript example.r
Full example
Connect to CrateDB and CrateDB Cloud using R.