Mailing-List: contact hbase-user-help@hadoop.apache.org; run by ezmlm
Precedence: bulk
Reply-To: hbase-user@hadoop.apache.org
Received-SPF: pass (athena.apache.org: domain of saint.ack@gmail.com
 designates 209.85.221.184 as permitted sender)
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=mime-version:sender:in-reply-to:references:date
         :x-google-sender-auth:message-id:subject:from:to:content-type
         :content-transfer-encoding;
        b=sT1l9lQIhTPBFV897zngvp0KlLLIWSoq/1IGrv5j4V+dSBDC3BCqi90+fZLuGV0rnJ
         v74CEW57pTZ+lpn725ZL5JT/e3T5CPH/Rf/Dvcwsost9iyl/TNX4vftlnKiHkC8XBYmX
         +b43kGipZaeyBBa3vqHMF66atyKnTsTSVht3Y=
MIME-Version: 1.0
Sender: saint.ack@gmail.com
In-Reply-To: <199D57B3-882A-48FE-96EC-D5A5D851D397@3crowd.com>
References: <8FF5F37F-7A4B-472B-982E-CCF8366BAFD2@3crowd.com>
	 <519188da1002111225i62790ebfgaaf399a15556ed53@mail.gmail.com>
	 <7844CA38-7835-4B2D-AD2B-1A189C34ED26@3crowd.com>
	 <7c962aed1002111427ved4e131ua318d19a080e0986@mail.gmail.com>
	 <199D57B3-882A-48FE-96EC-D5A5D851D397@3crowd.com>
Date: Thu, 11 Feb 2010 15:46:15 -0800
Message-ID: <7c962aed1002111546m5f474a19i8bef39c85beb893f@mail.gmail.com>
Subject: Re: request for mapreduce with hbase examples
From: Stack <stack@duboce.net>
To: hbase-user@hadoop.apache.org
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

On Thu, Feb 11, 2010 at 3:07 PM, David Hawthorne <dhawth@3crowd.com> wrote:
> Perhaps. =A0I figured it would be easier to go mapreduce -> hbase instead=
 of
> mapreduce -> output file in hdfs -> load output file into hbase as a
> separate job. =A0Then again, for performance, maybe hdfs -> hbase is bett=
er
> than mapreduce -> hbase and I should just plan to do that instead.
>

There is a bit of a miscommunication going on here I think.

For a "mapreduce to hbase" example, see the task in the Importer
class.  See how it configures an input that in this case is files in
hdfs but it could be anything -- just change the jobs configuration --
and then see how it hooks up TableOutputFormat to catch the map
emissions into hbase: i.e. "mapreduce to hbase".

St.Ack

>
> On Feb 11, 2010, at 2:27 PM, Stack wrote:
>
>> On Thu, Feb 11, 2010 at 12:38 PM, David Hawthorne <dhawth@3crowd.com>
>> wrote:
>>>
>>> I was under the impression that you could read from/write to an hbase
>>> table
>>> from within a mapreduce job. =A0Import and Export look like methods for
>>> reading HDFS files into hbase and dumping hbase into an HDFS file.
>>>
>>
>> Yes. =A0Isn't that what you want? =A0Export shows how to use hbase as a
>> mapreduce source and Import as a mapreduce sink.
>> St.Ack
>>
>>
>>
>>> On Feb 11, 2010, at 12:25 PM, Guohua Hao wrote:
>>>
>>>> Hello there,
>>>>
>>>> Did =A0you take a look at the Import and Export classes under package
>>>> org.apache.hadoop.hbase.mapreduce? They are mostly using new APIs in m=
y
>>>> mind. Correct me if I am wrong.
>>>>
>>>> Thanks,
>>>> Guohua
>>>>
>>>> On Thu, Feb 11, 2010 at 2:13 PM, David Hawthorne <dhawth@3crowd.com>
>>>> wrote:
>>>>
>>>>> I'm looking for some examples for reading data out of hbase for use
>>>>> with
>>>>> mapreduce and for inserting data into hbase from a mapreduce job. =A0=
I've
>>>>> seen
>>>>> the example shipped with hbase, and, well, it doesn't exactly make
>>>>> things
>>>>> click for me. =A0It also looks like it's using the old API, so maybe
>>>>> that's
>>>>> why.
>>>>>
>>>>> Can someone please send some example code for reading/writing from/to
>>>>> hbase
>>>>> with a mapreduce job? =A0The more examples the better.
>>>>>
>>>>> Thanks!
>>>>>
>>>
>>>
>
>