If I take the exact same SlicePredicate that fails in the Hadoop example, and pass it in to a multiget_slice, the data is returned successfully. So it appears the problem does lie somewhere in the tie-in to Hadoop.
Can you reproduce outside the Hadoop environment, i.e. w/ Thrift code?
On Mon, May 3, 2010 at 5:49 AM, Mark Schnitzius
> 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.
> 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?
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support