The cassandra column family input format will go over a an entire column family sending a slice of a row into a mapper at a time. From there there's a lot you can do. As far as how you aggregate data together, I'd suggest experimenting with the latest version of Pig which thankfully supports the new input format. It gives you a SQL'esque syntax for manipulating the data and is probably the easiest way to experiment.
On Thu, Jun 24, 2010 at 11:01 AM, Atul Gosain <atul.gos...@gmail.com> wrote: > Hi > What kind of Map Reduce support is provided for Cassandra ? > Can i get some columns from different rows and then aggregate them up > together. Its basically aggregation of statistics for various devices > connected to a network manager. Is it a right kind of use case to be > supported by MR ? > Thanks > Atul
