[R] Reading huge chunks of data from MySQL into Windows R

[hadley wickham]

> In my (limited) experience R is more powerful concerning data manipulation. An example: I have a vector holding a user id. Some user ids can appear more than once. Doing SELECT COUNT(DISTINCT userid) on MySQL will take approx. 15 min. Doing length(unique(userid)) will take (almost) no time...

I think you have it around the wrong way - or you don't have indexes
set up in mysql.  If you're dealing with large quanities of data I'd
strongly recommend learning about sql indexes as it will save you a
LOT of time.

Hadley