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From Dave Hardcastle <>
Subject Keys with identical timestamps
Date Mon, 09 Feb 2015 20:49:06 GMT

Could someone clarify whether the following statement from the manual - "If
two inserts are made into Accumulo with the same rowID, column, and
timestamp, then the behavior is non-deterministic" - applies even if the
versioning iterator is off? Is the non-determinism the fact that the order
is undetermined if two identical inserts are made and all versions are kept?

I have an application where the key corresponds to an object and a time
range, and the value is properties of the object over that time range. The
time range is stored in the column qualifier, but I also put the end of the
time range as the timestamp of the key. I frequently get data late, and so
create a key and insert that, but that key may already exist in the table.
When multiple identical versions get put in, the values are aggregated
using a combiner. This seems to be working fine. But maybe I shouldn't be
assuming that Accumulo won't silently drop one of the two keys?



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