[EMAIL PROTECTED] wrote:
We decided that it is impossible in hadoop to have different input/output
types for map and reduce. Then we decided to use another scheme. This scheme
assumes to run two jobs. First job has map function, second job has reduce
task. These jobs have different classes for input and output parameters. New
map and reduce will do the same as described above.
You can use ObjectWritable to pass any type of Writable inside it. This
way you can mix/match different input/output types easily. The overhead
of this wrapping is probably still smaller than submitting another job
just to change the types...
Please take a look at Indexer.java, where this trick is used.
--
Best regards,
Andrzej Bialecki <><
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