writing tables to Postgresql using rPostgreSQL when the database name is all capital letters
library(RPostgreSQL)
con <- dbConnect(PostgreSQL(), host="myhost",
                 user= "postgres", password="myPass", dbname="DATA")
dbWriteTable(con, "test", myDf)

Error in postgresqlExecStatement(conn, statement, ...) :
  RS-DBI driver: (could not Retrieve the result : ERROR:  no schema has been selected to create in
)
[1] FALSE

edd@max:~$ createdb DATA
edd@max:~$ psql DATA
psql (8.4.8)
Type "help" for help.

DATA=# q
edd@max:~$

R> library(RPostgreSQL)
R> con <- dbConnect(PostgreSQL(), host="localhost", user= "edd",
+                   password=".....", dbname="DATA")
R> con
<PostgreSQLConnection:(21936,0)>
R> dbWriteTable(con, "quicktest", cars)
[1] TRUE
R>

DATA=# select * from quicktest limit 5;
 row_names | speed | dist
-----------+-------+------
 1         |     4 |    2
 2         |     4 |   10
 3         |     7 |    4
 4         |     7 |   22
 5         |     8 |   16
(5 rows)

DATA=#