Thank you for your response. To clarify, I don't mind if R loads the data (in the background), but was hoping to have to only specify the query as a simple request and the list of input files. I'd like to do this relatively efficiently, so searching across ~100 RData files (10 to 100 KB each) only takes many seconds and not lots of minutes or hours.
-----Original Message----- From: David Winsemius [mailto:dwinsem...@comcast.net] Sent: Friday, July 15, 2011 11:42 AM To: Bhushan, Vipul Cc: r-help@r-project.org Subject: Re: [R] Querying RData Files, SQL style? On Jul 15, 2011, at 10:29 AM, Bhushan, Vipul wrote: > Hello. Is there a package or functionality available somewhere which > will allow for complex searches (such as what SQL can do) of > collections of RData files? Search capability within a given RData > file at a time (which could be put in a loop) would be good, but the > capability to perform joins to data across multiple RData files > would be great. These queries might be ad-hoc, so writing an R > program to get(load(...)) each file and customize the search in home- > grown R code isn't feasible. As I read the question it appears that your are not expecting to load the data into R and are rather asking for a program other than R (or Rscript or littler) to read .Rdata files and perform database joins. As I understand it, that is not available. As I understand it, there is not even a package that can look at .Rdata files for their object names and structure without actual loading them. Hoping to be corrected on either of these points. > > This shouldn't be dependent on environment details, but just in > case: I'm running version 2.13.0 in a Unix environment (but could > easily run in Windows too). > > Thanks very much. -- David Winsemius, MD West Hartford, CT ______________________________________________ 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.
