Hi, How are the column visibility elements stored in Accumulo. Is there a kind of compression that is used to save space or are all the elements for each key value paired stored as is. A pointer to the region of the code that i should look at for the implementation will also be helpful. Thanks Sitaraman
The column visibility is stored as a bytes on disk, derived from the entire visibility expression. In theory this may seem like a lot of space, but in practice it turns out to be fine for a couple of reasons.
First, RFiles employ relative key encoding, so if the visibility is the same in two consecutive keys, then the second one is simply omitted. Also, RFiles are use gz encoding by default. If you have a few similar (repeated) text strings to represent your visibilities, then they will compress very well.
However, if you have lots of different visibilities, then you may not end up gaining much from the storage tricks we employ.
Mike On Mon, Feb 17, 2014 at 10:30 PM, Sitaraman Vilayannur < [EMAIL PROTECTED]> wrote:
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