Hi,
Modularity!
I've always had the same question before. However, Tom White put that
thought to rest:
"It’s possible to make map and reduce functions even more composable
than we have done. A mapper commonly performs input format parsing,
projection (selecting the relevant fields), and filterin
On Fri 28 Sep 2012 09:39:13 AM EDT, Harsh J wrote:
Modularity!
Exactly! Write a mapper that operates as a filter on something about
your keys, then use it in whatever jobs you want. Your job needs to
operate on data subset A? chain it with the filter mapper that picks
out A. Your next one