[R] string problems in R

[Muting Zhang]

Hello all

I have been working on my thesis using R. I am a newbie to R and met a problem
that bothered me for a while due to my lack of acquaintance of R.

I am using R to query from SQL. I got a list of crsp_fundno of G-style mutual
funds which is still alive. I use the following codes and got what I want:

library(RODBC)
channel<-odbcConnect("CRSPFUND")
g.crspfundno<-sqlQuery(channel,"select crsp_fundno from Fund_style where
wbrger_obj_cd = 'G'order by crsp_fundno")
g.crspfundno (got crsp_fundno of G-style fund from Fund_style table)
y.crspfundno<-sqlQuery(channel,"select crsp_fundno from Fund_hdr where dead_flag
= 'N'and end_dt=20091231 order by crsp_fundno")
y.crspfundno (got crsp_fundno of still alive fund from Fund_hdr table)
g$key<-paste(g.crspfundno$crsp_fundno)
y$key<-paste(y.crspfundno$crsp_fundno)
v.fundno<-intersect(g$key,y$key) (using intersect to get crsp_fundno of G-style
mutual funds which is still alive.)
v.fundno

What i need to do next is using the v.fundno I got to query from another table
"Monthly_return" to get the mret coresponding to every v.fundno.
I have only a basic idea of the code:
for (i in 1:length(v.fundno)){
gmret<-sqlQuery(channel,"select mret from Monthly_returns where crsp_fundno =
toString(v.fundno[i])")
}
gmret
R gave me an error with undefined function "toString"
I know there should be some details added in to get it right,like define an
object or how to convert number to string..

I would be appreciated if anyone gives me any clue about it.

Muting