Access in-memory SQL database in R.

Source: https://cran.r-project.org/web/packages/RPostgres/readme/README.html

library(DBI)
library(RPostgres)
library(rstudioapi)
con <- dbConnect(Postgres(), host='localhost', port=askForSecret("port(e.g. 5432)"), dbname=askForSecret("database name"), user='postgres', password = rstudioapi::askForSecret("password"))
db_tables <- dbListTables(con)
sprintf("The database has %d tables.", length(db_tables))
## [1] "The database has 15 tables."
sprintf("The first table is `%s`.", db_tables[1])
## [1] "The first table is `age`."
dbReadTable(con, "age")
##    agelvl      agelvlt
## 1       A Less than 20
## 2       B        20-24
## 3       C        25-29
## 4       D        30-34
## 5       E        35-39
## 6       F        40-44
## 7       G        45-49
## 8       H        50-54
## 9       I        55-59
## 10      J        60-64
## 11      K   65 or more
## 12      Z  Unspecified
query_1 <- dbSendQuery(con, "SELECT * FROM supervisor")
dbFetch(query_1)
##   supertyp      supertypt supervis                    supervist
## 1        1     Supervisor        2      2-SUPERVISOR OR MANAGER
## 2        2         Leader        6                     6-LEADER
## 3        2         Leader        7                7-TEAM LEADER
## 4        3 Non-Supervisor        4          4-SUPERVISOR (CSRA)
## 5        3 Non-Supervisor        5 5-MANAGEMENT OFFICIAL (CSRA)
## 6        3 Non-Supervisor        8        8-ALL OTHER POSITIONS
## 7        4    Unspecified        *                *-UNSPECIFIED
dbClearResult(query_1)
dbDisconnect(con) # disconnect and exit