On Thu, Apr 21, 2011 at 6:32 AM, subodh agrawal <subodh.iitr at gmail.com> wrote:
Please comment on thses two queries. 1) While converting field of data type "date" selected form postgres, RpgSQL gives error on windows ?when field value is null.
Thanks. This reproduces the error.
library(RpgSQL)
DF <- data.frame(a = c(1, NA, 2), b = c(Sys.Date() + 1:2, NA), c =
c("a", NA, "b"))
con <- dbConnect(pgSQL(), user = "whatever", password = "whatever",
dbname = "whatever")
dbWriteTable(con, "DF", DF)
2) How a field can be assigned NULL value in R . I couldn't found a way to write NULL value in database table row using RpgSQL. I used dbWriteTable function to write data to database. One workaround temporarily i did is to write "NULL" string in database and then update "NULL" to NULL using update SQL script.
Continuing from above the following works in the development version of RpgSQL (although the writeTable above is still a problem in the development version). The NA fields are stored as NULLs and then converted back to NAs. (In the released version the code below only works for character columns.) DF2 <- DF[-2] dbWriteTable(con, "DF2", DF2) dbGetQuery(con, "select * from DF") I can send you the development version if you need it now.
Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com