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HDFS >> mail # dev >> A question about reading one block


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Re: A question about reading one block
Please ignore the previous email which I did not describe the problem
clearly.

On Wed, Oct 31, 2012 at 3:05 PM, Vivi Lang <[EMAIL PROTECTED]> wrote:

> Hi, thks for the replying.
>
> Is there any function can help me to create a InputStream for a certain
> Block which stored in a certain datanode
> Thanks,
>
> On Sat, Oct 27, 2012 at 9:41 PM, Harsh J <[EMAIL PROTECTED]> wrote:
>
>> Vivi,
>>
>> Assuming you know how to get the block info out of a file's metadata,
>> opening a file for read (with FileSystem.open API, etc.) with an
>> offset and length set to to match that of a block, will open and read
>> only that block.
>>
>> On Sat, Oct 27, 2012 at 2:19 AM, Vivi Lang <[EMAIL PROTECTED]> wrote:
>> > Hi guys,
>> >
>> > I am writing a program which need the data of several specific blocks (I
>> > know the blockinfo of those blocks), if I use the Hadoop 0.20, is there
>> > any  funtion which can help me to retrieve the content of block?
>> >
>> > Thanks,
>> > Vivi
>>
>>
>>
>> --
>> Harsh J
>>
>
>
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