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R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
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>
> ## First rough version of a test script
> ##
> ## Assumes that
> ## a) PostgreSQL is running, and
> ## b) the current user can connect
> ## both of which are not viable for release but suitable while we test
> ##
> ## Dirk Eddelbuettel, 02 Jul 2008
> ## 21 Oct 2008 make conditional on environment variables
>
> ## only run this if this env.var is set correctly
> if (Sys.getenv("POSTGRES_USER") != "" & Sys.getenv("POSTGRES_HOST") != "" & Sys.getenv("POSTGRES_DATABASE") != "") {
+
+ ## try to load our module and abort if this fails
+ stopifnot(require(RPostgreSQL))
+
+ ## load the PostgresSQL driver
+ drv <- dbDriver("PostgreSQL")
+ ## can't print result as it contains process id which changes print(summary(drv))
+
+ ## connect to the default db
+ con <- dbConnect(drv,
+ user=Sys.getenv("POSTGRES_USER"),
+ password=Sys.getenv("POSTGRES_PASSWD"),
+ host=Sys.getenv("POSTGRES_HOST"),
+ dbname=Sys.getenv("POSTGRES_DATABASE"),
+ port=ifelse((p<-Sys.getenv("POSTGRES_PORT"))!="", p, 5432))
+
+ ## run a simple query and show the query result
+ res <- dbGetQuery(con, paste("select datname,encoding,datallowconn from pg_database",
+ "where datname like 'template%' order by datname"))
+ print(res)
+
+ ## and disconnect
+ dbDisconnect(con)
+ }
Loading required package: RPostgreSQL
Loading required package: DBI
datname encoding datallowconn
1 template0 6 FALSE
2 template1 6 TRUE
[1] TRUE
>
> proc.time()
user system elapsed
0.407 0.032 0.428
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