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From "Owen O'Malley" <omal...@apache.org>
Subject Re: Reduce output is strange
Date Tue, 03 Apr 2012 15:29:33 GMT
On Tue, Apr 3, 2012 at 8:25 AM, Pedro Costa <psdc1978@gmail.com> wrote:
> What I want to ask is:
>
> - how do I read the values from sequence files that are block, or record
> compressed, or uncompressed?

You use the SequenceFile.Reader class.

> - how do I know if the sequence file is block compressed, record
> compressed, or uncompressed?

You use the SequenceFile.Reader class.

>
> - how do I know if it's a sequence file or a Textfile?

SequenceFile's always have "SEQ" followed by the version in the first 4 bytes.

-- Owen

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