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Subject RE: TimeSpan Iterator
Date Tue, 28 Aug 2012 16:51:14 GMT


Your comment "Users should be aware that this is not an efficient
operation, though." may help me decide if my current use of a secondary
time index is better then.  Right now I maintain a table that has
timestamps as the rowid whose values are the rowid in a metadata table.
Therefore I do one range scan based on the timestamp.  Then a second
lookup of the metadata rowid.  Is this more efficient?  


From: Billie Rinaldi [] 
Sent: Tuesday, August 28, 2012 11:46
Subject: Re: TimeSpan Iterator


On Tue, Aug 28, 2012 at 6:33 AM, John Armstrong <> wrote:

On 08/28/2012 09:26 AM, wrote:

Does anyone know of a TimeSpan Iterator that will fetch rows based on
the accumulo timestamp?


We actually wrote our own TimestampRangeIterator and
TimestampSetIterator classes.  I don't know if 1.4 has any in the core
libraries.  It's not very hard though.

There's a TimestampFilter in org.apache.accumulo.core.iterators.user in
1.4.  It uses a range of timestamps.  Users should be aware that this is
not an efficient operation, though.


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