Index files map keys (not tokens) to offsets in the data file. A range scan uses the index file to seek to the start position in the data file and then does a partial scan of the data file.
Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 9/07/2012, at 7:24 PM, prasenjit mukherjee wrote: > Thanks for the response. Further questions inline.. > > On Mon, Jul 9, 2012 at 11:50 AM, samal <samalgo...@gmail.com> wrote: >>> 1. With RandomPartitioner, on a given node, are the keys sorted by >>> their hash_values or original/unhashed keys ? >> >> hash value, > > 1. Based on the second answer in > http://stackoverflow.com/questions/2359175/cassandra-file-structure-how-are-the-files-used > it seems that the index-file ( for a given ssTable ) contains the > row-key ( and not the hash_keys ). Or may be I am missing something. > > 2. Do the "keys" in Index-file ( ref > http://hi.csdn.net/attachment/201111/28/0_1322461982l3D8.gif ) > actually contain : hash(row_key)+row_key or something like that ? > Otherwise you need a separate mapping info from hash_bucket -> rows > for reading. > > -Thanks, > Prasenjit
