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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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>
> ## dbExists test with schema name: reported as Issue 3 at
> ## http://code.google.com/p/rpostgresql/issues/detail?id=3
> ## and based on an earlier email by Prasenjit Kapat
> ##
> ## 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")
+
+ ## 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 dbExists
+ cat("Does rockdata exist? ")
+ print(res <- dbExistsTable(con, "rockdata"))
+
+ ## this should return TRUE but did not -- does now after patch
+ cat("Does public.rockdata exist? ")
+ print(res <- dbExistsTable(con, "public.rockdata"))
+
+ ## cleanup
+ if (dbExistsTable(con, "rockdata")) {
+ print("Removing rockdata\n")
+ dbRemoveTable(con, "rockdata")
+ }
+
+ ## and disconnect
+ dbDisconnect(con)
+ }
Loading required package: RPostgreSQL
Loading required package: DBI
Does rockdata exist? [1] TRUE
Does public.rockdata exist? [1] FALSE
[1] "Removing rockdata\n"
[1] TRUE
>
> proc.time()
user system elapsed
0.493 0.035 0.572
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