Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Hadoop >> mail # user >> Problem with using BinSedesTuple as Mapper key


Copy link to this message
-
Re: Problem with using BinSedesTuple as Mapper key
Hi Gayatri,
Looks like you might want to use a low-level enhancement of the default
Hadoop API called Pangool (http://pangool.net) which uses tuples and
simplifies grouping by, sorting by and joining datasets in Hadoop.

On Mon, Apr 23, 2012 at 7:30 AM, Gayatri Rao <[EMAIL PROTECTED]> wrote:

> Hello,
>
> I am using BinSedesTuple as a mapper key to emit a tuple of values. But
> somehow same keys do not go to the same reducer and I do not get
> aggregates.
> Is it not suggested to use it as a mapper key?
>
> For example in my mapper I emit
>
> Mapper:
> Output key : BinSedesTuple  value: int
>
>
> Example output:
> tuple.append(url);
> tuple.append(category);
>
> Reducer:
> Input key: BinSedesTuple value: int
> Output key: Text value: int
>
> Example output:
> url1 category1 3
> url1 category1 2
>
> In the reducer output I get output with multiple keys being the same. My
> expected output is
> url1 category 5
>
> Any ideas what might be wrong?
>
>
> Thanks,
> Gayatri
>