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From Mark Schnitzius <>
Subject Feeding in specific Cassandra columns into Hadoop
Date Mon, 03 May 2010 10:49:51 GMT
Hi all...  I am trying to feed a specific list of Cassandra column names in
as input to a Hadoop process, but for some reason it only feeds in some of
the columns I specify, not all.

This is a short description of the problem - I'll see if anyone might have
some insight before I dump a big load of code on you...

1.  I've uploaded a bunch of data into Cassandra; the column names as longs
(dates, basically) converted to byte[8].

2.  I can successfully set a SlicePredicate using setSlice_range to return
all the data for a set of columns.

3.  However, if I instead call setColumn_names on the SlicePredicate, only
some of the specified columns get fed into Hadoop.

4.  This faulty behavior is repeatable, with the same columns going missing
each time for the same input parameters.

5.  For the values that fail, I've made fairly certain that the value for
the column name is getting inserted successfully, and that the exact same
column name is specified in the call to setColumn_names.

Any clues?


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