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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)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> ## dbGetQuery test with optional parameters
> ##
> ## 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
>
> ## 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))
+ stopifnot(require(datasets))
+
+ ## load the PostgresSQL driver
+ drv <- dbDriver("PostgreSQL")
+
+ ## 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))
+
+
+ if (dbExistsTable(con, "rockdata")) {
+ print("Removing rockdata\n")
+ dbRemoveTable(con, "rockdata")
+ }
+
+ dbWriteTable(con, "rockdata", rock)
+
+ ## run a simple query and show the query result
+ res <- dbGetQuery(con, "SELECT * FROM rockdata WHERE peri > $1 LIMIT 10", 4000)
+ print(res)
+ res <- dbGetQuery(con, "SELECT * FROM rockdata WHERE peri > $1 AND shape < $2 LIMIT $3", c(4000, 0.2, 10))
+ print(res)
+
+
+ ## cleanup
+ if (dbExistsTable(con, "rockdata")) {
+ print("Removing rockdata\n")
+ dbRemoveTable(con, "rockdata")
+ }
+
+ ## and disconnect
+ dbDisconnect(con)
+ }
Loading required package: RPostgreSQL
Loading required package: DBI
row.names area peri shape perm
1 6 7979 4010.15 0.167045 17.1
2 7 9333 4345.75 0.189651 17.1
3 8 8209 4344.75 0.164127 17.1
4 11 9364 4480.05 0.150944 119.0
5 13 10651 4036.54 0.228595 82.4
6 17 10962 4608.66 0.204314 58.6
7 18 10743 4787.62 0.262727 58.6
8 19 11878 4864.22 0.200071 58.6
9 20 9867 4479.41 0.144810 58.6
10 22 11876 4353.14 0.291029 142.0
row.names area peri shape perm
1 6 7979 4010.15 0.167045 17.1
2 7 9333 4345.75 0.189651 17.1
3 8 8209 4344.75 0.164127 17.1
4 11 9364 4480.05 0.150944 119.0
5 20 9867 4479.41 0.144810 58.6
[1] "Removing rockdata\n"
[1] TRUE
>
> proc.time()
user system elapsed
0.470 0.036 0.550
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