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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.
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Type 'license()' or 'licence()' for distribution details.
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'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
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Type 'q()' to quit R.
>
> ## dbWriteTable test
> ##
> ## 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, 10 Sep 2009
>
> ## 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")
+
+ ## create two independent connections
+ 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, "tmptest")) {
+ cat("Removing tmptest\n")
+ dbRemoveTable(con, "tmptest")
+ }
+ # create temporary table (as a copy of any existing one)
+ # dbGetQuery(con, "BEGIN TRANSACTION")
+ cat("create temp table tmptest with dbGetQuery\n")
+ dbGetQuery(con, "CREATE TEMP TABLE tmptest (f1 int)")
+
+ # query temp table
+ rs<-dbGetQuery(con, "SELECT * from tmptest")
+ print(rs)
+
+ cat("create temp table tmptest with dbSendQuery\n")
+ dbSendQuery(con, "CREATE TEMP TABLE tmptest2(f2 int)")
+
+ # query temp table
+ rs2<-dbGetQuery(con, "SELECT * from tmptest2")
+ print(rs2)
+ ## and disconnect
+ dbDisconnect(con)
+
+ 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, "tmptest")) {
+ cat("FAIL tmptest persisted after disconnection\n")
+ cat("Removing tmptest\n")
+ dbRemoveTable(con, "tmptest")
+ }else{
+ cat("PASS tmptest disappeared after disconnection\n")
+ }
+ dbDisconnect(con)
+ }
Loading required package: RPostgreSQL
Loading required package: DBI
create temp table tmptest with dbGetQuery
data frame with 0 columns and 0 rows
create temp table tmptest with dbSendQuery
data frame with 0 columns and 0 rows
PASS tmptest disappeared after disconnection
[1] TRUE
>
> proc.time()
user system elapsed
0.442 0.042 0.504
|
