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From Jeremy Hanna <jeremy.hanna1...@gmail.com>
Subject Re: Hadoop Word Count Super Column Example?
Date Tue, 19 Oct 2010 15:44:46 GMT
It's relatively straightforward, the current mapper gets a map of column names to IColumns.
 The SuperColumn implements the IColumn interface.  So you would probably need both the super
column name and the subcolumn name to get at it, but you just need to cast the IColumn to
a super column and handle it from there.

On Oct 19, 2010, at 10:31 AM, Frank LoVecchio wrote:

> I have a Hadoop installation working with a cluster of 0.7 Beta 2 Nodes, and got the
WordCount example to work using the standard configuration.  I have been inserting data into
a Super Column (Sensor) with TimeUUID as the compare type, it looks like this:
> 
> get Sensor['DeviceID:Sensor']
> => (super_column=795a4da0-d8ac-11df-9a2c-12313d06187c,
>      (column=sub_sensor1, value=39.742538, timestamp=1287182112633000) 
>      (column=sub_sensor2, value=-104.912474, timestamp=1287182112633000) 
>      (column=mac_address, value=DEADBEEFFEED, timestamp=1287182112633000)) 
> 
> Is there a Word Count example for super columns?  I am trying to count the number of
occurrences of "DEADBEEFFEED", much like "word1" in the column example.  
> 
> Thanks,
> 
> Frank LoVecchio
> Software Engineer, Isidorey LLC
> isidorey.com
> 
> franklovecchio.com
> rodsandricers.com


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