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Posted to common-user@hadoop.apache.org by Roldano Cattoni <ca...@fbk.eu> on 2009/03/13 07:14:16 UTC
how to preserve original line order?
The task should be simple, I want to put in uppercase all the words of a
(large) file.
I tried the following:
- streaming mode
- the mapper is a perl script that put each line in uppercase (number of
mappers > 1)
- no reducer (number of reducers set to zero)
It works fine except for line order which is not preserved.
How to preserve the original line order?
I would appreciate any suggestion.
Roldano
Re: how to preserve original line order?
Posted by Miles Osborne <mi...@inf.ed.ac.uk>.
associate with each line an identifier (eg line number) and afterwards
resort the data by that
Miles
2009/3/13 Roldano Cattoni <ca...@fbk.eu>:
> The task should be simple, I want to put in uppercase all the words of a
> (large) file.
>
> I tried the following:
> - streaming mode
> - the mapper is a perl script that put each line in uppercase (number of
> mappers > 1)
> - no reducer (number of reducers set to zero)
>
> It works fine except for line order which is not preserved.
>
> How to preserve the original line order?
>
> I would appreciate any suggestion.
>
> Roldano
>
>
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