[R-sig-DB] RdbiPgSQL: Sub-second support for type conversion

[Dirk Eddelbuettel]

Brian Ripley did a lot of really nice work a year ago to support milli- (and
even micro-) second resolutions in R's POSIXt types.  

Trying to read such data back from Postgresql, I was getting

   > Foo <- dbReadTable(db, someTable)
   Warning messages:
   1: Coercing PGSQL type 1114 to character in:
   rpgsql.cast.values.default(data.col) 

for columns of type timestamp (actually: 'timestamp without time zone'). 
As I use

   options("digits.secs"=7)

a simple Sys.time() returns strings such

   > Sys.time()
   [1] "2007-03-05 13:28:39.260931 CST"


Now, I just had a really quick look at the RdbiPgSQL sources, and it turns
out that I can solve my problem with a simple one-liner similar to what is
already at the end of R/types.R:

   ## indented just for the mail
   rpgsql.cast.values.1114 <- function(x) { 
      as.POSIXct(strptime(x, "%a %b %d %H:%M:%OS %Y")) 
   }

But i presume that the format string is locale-dependent.  Is there a clever
way to code the format in a way that will work in other settings?

Dirk

-- 
Hell, there are no rules here - we're trying to accomplish something. 
                                                  -- Thomas A. Edison