Hi: One option is to read your data frame into R and then use your SQL code in conjunction with the sqldf package. It uses SQLite as its engine.
HTH, Dennis On Mon, Sep 27, 2010 at 4:29 AM, Xin Zhang <xin.zh...@gmail.com> wrote: > Suppose I have the following data frame (df): > > Year Price > ------------------- > 2001 10 > 2002 20 > 2003 30 > > I would like to produce another data frame like this: > > a.Year a.Price b.Year b.Price > ---------------------------------------------------- > 2002 20 2001 10 > 2003 30 2001 10 > 2003 30 2002 20 > > In SQL, this can be done as > > select a.*, b.* > from df as a, df as b > where a.Year > b.Year > > How do I do this efficiently in R? > > Many thanks. > > ______________________________________________ > 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 > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ 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 and provide commented, minimal, self-contained, reproducible code.