[R] Sampling from a Postgres database

[Bart Joosen]

One way could be to first select only the unique ID's, sample this and then
select only the relevant records:

strQuery = "SELECT ID from tblFoo;"
IDs <- sqlQuery(channel, strQuery)
sample.IDs <- sample(IDs,10)
strQuery = paste("SELECT ID from tblFoo WHRE ID IN(", sample.IDs, ");")
IDs <- sqlQuery(channel, strQuery)

Bart



christiaan pauw-2 wrote:
> 
> Hi Everybody
> 
> Is there a way in which one can use the RPostgreSQL package to take a
> sample
> from a table in Postgres database without having to read the whole table
> into R
> 
> regards
> Christiaan
> 
> 	[[alternative HTML version deleted]]
> 
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