create string of comma-separated content of vector

Hi,

how do I create a string of the comma-separated content of a vector?

I've got the vector i with several numeric values as content:

str(i)

num 99

and want to create a SQL statement to look like the following where
the part '(2, 4, 6, 7)' should be
the content of the vector i:
select * from  [biomass_data$] where site_no in (2, 4, 6, 7)

Here my approach (which doesn't work):
site_all_data <=  sqlQuery(channel, "select * from  [biomass_data$]
where site_no in (",paste(i,sep=","),") )


sorry for spaming so much today to the mailing list...

-Katharina

--
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