RSQLite

Embeds the SQLite database engine in R, providing a DBI-compliant interface. SQLite is a public-domain, single-user, very light-weight database engine that implements a decent subset of the SQL 92 standard, including the core table creation, updating, insertion, and selection operations, plus transaction management.

You can install the latest released version from CRAN with:

install.packages("RSQLite")

Or install the latest development version from GitHub with:

# install.packages("devtools")
devtools::install_github("rstats-db/RSQLite")

To install from GitHub, you'll need a development environment.

Basic usage

library(DBI)
# Create an ephemeral in-memory RSQLite database
con <- dbConnect(RSQLite::SQLite(), ":memory:")

dbListTables(con)

## character(0)

dbWriteTable(con, "mtcars", mtcars)

## [1] TRUE

dbListTables(con)

## [1] "mtcars"

dbListFields(con, "mtcars")

##  [1] "row_names" "mpg"       "cyl"       "disp"      "hp"       
##  [6] "drat"      "wt"        "qsec"      "vs"        "am"       
## [11] "gear"      "carb"

dbReadTable(con, "mtcars")

##                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
## Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
## Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
## Datsun 710          22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
## Hornet 4 Drive      21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
## Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2
## Valiant             18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
## Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
## Merc 240D           24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
## Merc 230            22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
##  [ reached getOption("max.print") -- omitted 23 rows ]

# You can fetch all results:
res <- dbSendQuery(con, "SELECT * FROM mtcars WHERE cyl = 4")
dbFetch(res)

##                 mpg cyl  disp  hp drat    wt  qsec vs am gear carb
## Datsun 710     22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
## Merc 240D      24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
## Merc 230       22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
## Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
## Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
## Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
## Toyota Corona  21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1
## Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
## Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
##  [ reached getOption("max.print") -- omitted 2 rows ]

dbClearResult(res)

## [1] TRUE

# Or a chunk at a time
res <- dbSendQuery(con, "SELECT * FROM mtcars WHERE cyl = 4")
while(!dbHasCompleted(res)){
  chunk <- dbFetch(res, n = 5)
  print(nrow(chunk))
}

## [1] 5
## [1] 5
## [1] 1

# Clear the result
dbClearResult(res)

## [1] TRUE

# Disconnect from the database
dbDisconnect(con)

## [1] TRUE

Acknowledgements

Many thanks to Doug Bates, Seth Falcon, Detlef Groth, Ronggui Huang, Kurt Hornik, Uwe Ligges, Charles Loboz, Duncan Murdoch, and Brian D. Ripley for comments, suggestions, bug reports, and/or patches.