I am pleased to announce the release of my first open source project . Openpivot is designed to efficiently reproduce the functionality of MS excel pivot tables. The problem of MS excel is that old versions (priori to 2007) cannot deal files larger than 65 000 rows. At work a lot of people are always writing scripts to pre-aggregate the data they have to then be able to play with it in excel.
Openpivot was written in c++ an I have been focusing on performance so that it can been used in large amount of data processing.
The principle is that you have a [large] csv file with headers and you would like to have an aggregated view of this file. You may want to aggregate a certain column or see the sum of a certain columns by entry of another column. Check it out on google code :
I will post a tutorial in a few days to show how to use it, and you will see that it is simple. So far it is a command line tool and only works on mac os and linux. I will try to have it compatible with windows when I get to a stable point.