In the example code from Pro Hadoop, is a sample map reduce job that uses mapside join to merge the files into a single output. It is part of the chapter 9 examples.
On Wed, Jul 8, 2009 at 4:55 PM, Ted Dunning <[email protected]> wrote: > On Wed, Jul 8, 2009 at 3:38 PM, Owen O'Malley <[email protected]> wrote: > > > > > On Jul 8, 2009, at 3:13 PM, Pankil Doshi wrote: > > > > Can anyone guide me to merge my output files from reducer to single file > >> in > >> HDFS. > >> > > > > The usual approach is to leave them as separate files. > > > Also, the need to merge often arises from a need to import the data into an > external database. That doesn't sound like your need because you already > know and have rejected dfs -cat. > > It may help to think of the containing directory as the actual file and the > files inside that directory as no more interesting than the inodes and > blocks that make up a normal unix file. > -- Pro Hadoop, a book to guide you from beginner to hadoop mastery, http://www.amazon.com/dp/1430219424?tag=jewlerymall www.prohadoopbook.com a community for Hadoop Professionals
