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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.
>
> ## 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")
+
+ ## 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")
+ }
+ cat("create incompatible table rockdata\n")
+ dbGetQuery(con, "CREATE TABLE rockdata (a int, b varchar(5))")
+
+ cat("write table to rockdata with append=TRUE\n")
+ try({res <-dbWriteTable(con, 'rockdata', rock, append=TRUE, overwrite=FALSE)
+ print(res)
+ if(res == FALSE){
+ cat("PASS as the return value is false\n")
+ }else{
+ cat("FAIL as the return value is true\n")
+ }
+ })
+
+ cat("write table to rockdata\n")
+ try({res <- dbWriteTable(con, 'rockdata', rock)
+ if(res == FALSE){
+ print(res)
+ cat("PASS as the return value is false\n")
+ }else{
+ cat("FAIL as the return value is true\n")
+ }
+ })
+
+ ## run a simple query and show the query result
+ res <- dbGetQuery(con, "select * from rockdata limit 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
create incompatible table rockdata
write table to rockdata with append=TRUE
Error in postgresqlpqExec(new.con, sql4) :
RS-DBI driver: (could not Retrieve the result : ERROR: column "row.names" of relation "rockdata" does not exist
)
write table to rockdata
[1] FALSE
PASS as the return value is false
data frame with 0 columns and 0 rows
[1] "Removing rockdata\n"
[1] TRUE
Warning message:
In postgresqlWriteTable(conn, name, value, ...) :
table rockdata exists in database: aborting assignTable
>
> proc.time()
user system elapsed
0.473 0.035 0.519
|
