Dear R wizards: I decided to take the advice in the R data import/export manual and want to learn how to work with SQL for large data sets. I am trying SQLite with the DBI and RSQLite database interfaces. Speed is nice. Alas, I am struggling to find a tutorial that is geared for the kind of standard operations that I would want in R. Simple things:
* how to determine the number of rows in a table. (Of course, I could select a row of data and then use this.) * how to insert a new column into my existing SQL table---say, the rank of another variable---and save it back. Am I supposed to create a new data frame, then save it as a new table, then delete the old SQL table? * how to save a revised version of my table in a different sort order (with or without deleting the original table). <-- I guess this is not appropriate, as I should think of SQL tables as unordered. I guess these would make nice little text snippets in the R Data import/export manual, too. help appreciated. regards, /ivo ______________________________________________ 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.
