Rhelpers:
I'd like to modify this RSQLite statement:
rs_stations<-dbSendQuery(con_stations, "select * from stations")
so that stations is actually an R variable, e.g.:
stations=c("stationA","stationB")
How would I modify the above statement to query from stations[[1]]
(aka "stationA")?
--j
?paste On Mon, May 10, 2010 at 6:21 PM, Jonathan Greenberg <greenberg@ucdavis.edu>wrote:> Rhelpers: > > I'd like to modify this RSQLite statement: > > rs_stations<-dbSendQuery(con_stations, "select * from stations") > > so that stations is actually an R variable, e.g.: > > stations=c("stationA","stationB") > > How would I modify the above statement to query from stations[[1]] > (aka "stationA")? > > --j > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? [[alternative HTML version deleted]]
?paste
See also,
http://rwiki.sciviews.org/doku.php?id=large_scale_data:lsdioi_sqchunk for
additional examples.
Assuming stations[1:2] are tables your database:
simpleQuery<- paste("SELECT * FROM", stations[1]) # should read the
whole
table when invoked
dbGetQuery(con_stations, simpleQuery)
Is this sort of what you had in mind?
Sincerely,
KeithC.
-----Original Message-----
From: Jonathan Greenberg [mailto:greenberg at ucdavis.edu]
Sent: Monday, May 10, 2010 4:21 PM
To: r-help
Subject: [R] dbSendQuery with R variables
Rhelpers:
I'd like to modify this RSQLite statement:
rs_stations<-dbSendQuery(con_stations, "select * from stations")
so that stations is actually an R variable, e.g.:
stations=c("stationA","stationB")
How would I modify the above statement to query from stations[[1]] (aka
"stationA")?
--j
Try this. If fn$ prefaces the function name, subject to certain rules
string which determine which arguments are re-interpreted,
interpolation somewhat like in perl occurs. Here we have enclosed
stations[[1]] in back quotes.
library(gsubfn)
stations <- c("stationA", "stationB")
rs_stations <- fn$dbSendQuery(con_stations, "select * from
`stations[[1]]`")
On Mon, May 10, 2010 at 6:21 PM, Jonathan Greenberg
<greenberg at ucdavis.edu> wrote:> Rhelpers:
>
> I'd like to modify this RSQLite statement:
>
> rs_stations<-dbSendQuery(con_stations, "select * from
stations")
>
> so that stations is actually an R variable, e.g.:
>
> stations=c("stationA","stationB")
>
> How would I modify the above statement to query from stations[[1]]
> (aka "stationA")?
>
> --j
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>