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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.
>
> ## dbExistsq test with schema name: reported as Issue 28 at
> ## http://code.google.com/p/rpostgresql/issues/detail?id=28
> ##
> ## 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, "rock.data")) {
+ cat("Removing rock'data\n")
+ dbRemoveTable(con, "rock.data")
+ }
+
+
+ dbWriteTable(con, "rock.data", rock)
+ ## run a simple dbExists
+ cat("Does rock.data exist? \n")
+ res <- dbExistsTable(con, "rock.data")
+ if(res){
+ cat("PASS: true\n")
+ }else{
+ cat("FAIL: false\n")
+ }
+
+ ##
+ cat("create schema testschema and change the search_path\n")
+
+ dbGetQuery(con, 'CREATE SCHEMA testschema')
+ dbGetQuery(con, 'SET search_path TO testschema')
+ cat("Does rock.data exist? \n")
+ res <- dbExistsTable(con, "rock.data")
+ if(res){
+ cat("FAIL: true despite search_path change\n")
+ }else{
+ cat("PASS: false as the search_path changed\n")
+ }
+
+ cat("Does testschema.\"rock.data\" exist? \n")
+ res <- dbExistsTable(con, c('testschema', "rock.data"))
+ if(res){
+ cat("FAIL: true despite testschema specified\n")
+ }else{
+ cat("PASS: false as the testschema specified\n")
+ }
+
+ cat("Does public.\"rock.data\" exist? \n")
+ res <- dbExistsTable(con, c('public', "rock.data"))
+ if(res){
+ cat("PASS: true despite search_path change\n")
+ }else{
+ cat("FAIL: false as the search_path changed\n")
+ }
+
+
+ cat("write in current schema\n")
+ dbWriteTable(con, "rock.data", rock)
+ cat("Does rock.data exist? \n")
+ res <- dbExistsTable(con, "rock.data")
+ if(res){
+ cat("PASS: true\n")
+ }else{
+ cat("FAIL: false\n")
+ }
+
+ ## cleanup
+ dbGetQuery(con, 'DROP TABLE "public"."rock.data"')
+ dbGetQuery(con, 'DROP TABLE "testschema"."rock.data"')
+ dbGetQuery(con, 'DROP schema "testschema"')
+
+ ## and disconnect
+ dbDisconnect(con)
+ }
Loading required package: RPostgreSQL
Loading required package: DBI
Does rock.data exist?
PASS: true
create schema testschema and change the search_path
Does rock.data exist?
PASS: false as the search_path changed
Does testschema."rock.data" exist?
PASS: false as the testschema specified
Does public."rock.data" exist?
PASS: true despite search_path change
write in current schema
Does rock.data exist?
PASS: true
[1] TRUE
>
> proc.time()
user system elapsed
0.512 0.048 0.663
|
