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MapReduce >> mail # dev >> Reduce output is strange


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Re: Reduce output is strange
On Tue, Apr 3, 2012 at 8:25 AM, Pedro Costa <[EMAIL PROTECTED]> 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
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB