On Tue, Aug 7, 2012 at 11:33 AM, Harsh J <ha...@cloudera.com> wrote: > Each write call registers (writes) a KV pair to the output. The output > collector does not look for similarities nor does it try to de-dupe > it, and even if the object is the same, its value is copied so that > doesn't matter. > > So you will get two KV pairs in your output - since duplication is > allowed and is normal in several MR cases. Think of wordcount, where a > map() call may emit lots of ("is", 1) pairs if there are multiple "is" > in the line it processes, and can use set() calls to its benefit to > avoid too many object creation.
Thanks! > > On Tue, Aug 7, 2012 at 11:56 PM, Mohit Anchlia <mohitanch...@gmail.com> > wrote: > > In Mapper I often use a Global Text object and througout the map > processing > > I just call "set" on it. My question is, what happens if collector > receives > > similar byte array value. Does the last one overwrite the value in > > collector? So if I did > > > > Text zip = new Text(); > > zip.set("9099"); > > collector.write(zip,value); > > zip.set("9099"); > > collector.write(zip,value1); > > > > Should I expect to receive both values in reducer or just one? > > > > -- > Harsh J >