Interesting... I haven't tried this yet.. but in this case what would you 
specify as the 'InputPath'?  I was under the assumption that a Job needs some 
kind of InputPath.. no?  I don't see a NullInputPath.  Is there something 
equivalent?



________________________________
From: Doug Meil <doug.m...@explorysmedical.com>
To: "hbase-u...@hadoop.apache.org" <hbase-u...@hadoop.apache.org>; 
"general@hadoop.apache.org" <general@hadoop.apache.org>
Sent: Mon, October 19, 2009 7:34:03 AM
Subject: RE: Question about MapReduce

Hi there-

I didn't see the option in the thread yet which seems pretty straightforward:

When setting up the job:

    Job job = new Job(conf, "my job");

...
        
    conf.setStrings("param", "param1");


And then in the map method:

      String paramVal = context.getConfiguration().get("param");


This is using Hadoop .20 syntax, the previous verison had a 'configure' method 
you had to implement.



-----Original Message-----
From: Something Something [mailto:luckyguy2...@yahoo.com] 
Sent: Thursday, October 15, 2009 2:31 PM
To: hbase-u...@hadoop.apache.org; Hadoop
Subject: Re: Question about MapReduce

1) I don't think TableInputFormat is useful in this case.  Looks like it's used 
for scanning columns from a single HTable.
2) TableMapReduceUtil - same problem.  Seems like this works with just one 
table.
3) JV recommended NLineInputFormat, but my parameters are not in a file.  They 
come from multiple files and are in memory.

I guess what I am looking for is something like... InMemoryInputFormat... 
similar to FileInputFormat & DbInputFormat.  There's no such class right now.

Worse comes to worst, I can write the parameters into a flat file, and use 
FileInputFormat - but that will slow down this process considerably.  Is there 
no other way?





________________________________
From: Mark Vigeant <mark.vige...@riskmetrics.com>
To: "hbase-u...@hadoop.apache.org" <hbase-u...@hadoop.apache.org>
Sent: Thu, October 15, 2009 7:21:40 AM
Subject: RE: Question about MapReduce

There is a tableInputFormat class in 
org.apache.hadoop.hbase.mapreduce.TableInputFormat

Also, if you want to use TableMapReduceUtil you probably want to have your 
mapper function extend TableMapper.

Check out the javadocs for more info: 
http://hadoop.apache.org/hbase/docs/current/api/index.html



-----Original Message-----
From: Something Something [mailto:luckyguy2...@yahoo.com] 
Sent: Thursday, October 15, 2009 1:37 AM
To: general@hadoop.apache.org; hbase-u...@hadoop.apache.org
Subject: Re: Question about MapReduce

If the answer is...

TableMapReduceUtil.initTableMapperJob

I apologize for the spam.  If this isn't the right way, please let me know.  
Thanks.


--- On Wed, 10/14/09, Something Something <luckyguy2...@yahoo.com> wrote:

From: Something Something <luckyguy2...@yahoo.com>
Subject: Question about MapReduce
To: general@hadoop.apache.org, hbase-u...@hadoop.apache.org
Date: Wednesday, October 14, 2009, 10:18 PM

I would like to start a Map-Reduce job that does not read data from an input 
file or from a database.  I would like to pass 3 arguments to the Mapper & 
Reducer to work on.  Basically, these arguments are keys on the 3 different 
tables on HBase.

In other words, I don't want to use FileInputFormat or DbInputFormat because 
everything I need is already on HBase. 

How can I do this?  Please let me know.  Thanks.


      

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