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  1. Cassandra
  2. CASSANDRA-2212

Cannot get range slice of super columns in reversed order

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Details

    • Bug
    • Status: Resolved
    • Normal
    • Resolution: Fixed
    • 0.6.13, 0.7.3
    • None
    • None
    • Fedore 11, Intel Core i5

    • Normal

    Description

      I cannot get range slice of super columns in reversed order. These data are stored in Cassandra in advance. On the other hand, range slice of these data in normal order can be acquired.

      You can reproduce the bug by executing attached programs.

      • 1. Start Cassandra daemon on localhost (number of thrift port is 9160)
      • 2. Create keyspace and column family, according to "create_table.cli",
      • 3. Execute "cassandra_sample_insert.py", storing pairs of row keys and super columns
      • 4. Execute "cassandra_sample_rangeslice.py" and get range slice of stored super columns
        "cassandra_sample_insert.py" and "cassandra_sample_rangeslice.py" require pycassa.

      You will need to execute 4."cassandra_sample_rangeslice.py" with following options so that you get range slice of super columns in reversed order.

      % python cassandra_sample_rangeslice.py -r 00082 00083

      On the other hand, to get range slice in normal order, you will need to use following options.

      % python cassandra_sample_rangeslice.py -f 00082 00083

      00082 and 00083 are the specified key range. Range slice can be acquired in normal order but, I cannot get it in reversed order.

      I assume that there may be a bug within the code for acquiring the index block of specified range. In fact, 00083 is included in gap between lastName of index block and firstName of next index block.

      Attachments

        1. 0001-Fix-IndexHelp.indexFor-for-reverse-query.patch
          7 kB
          Sylvain Lebresne
        2. 2212_0.6.patch
          7 kB
          Sylvain Lebresne
        3. cassandra_sample_insert.py
          1 kB
          Muga Nishizawa
        4. cassandra_sample_rangeslice.py
          0.9 kB
          Muga Nishizawa
        5. create_table.cli
          0.1 kB
          Muga Nishizawa

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            slebresne Sylvain Lebresne
            muga_nishizawa Muga Nishizawa
            Sylvain Lebresne
            Jonathan Ellis
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              Updated:
              Resolved:

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