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From Marc Reichman <>
Subject Re: Filtering on column qualifier
Date Thu, 22 Aug 2013 14:19:50 GMT
Extending looked like a bit of a boondoggle, because all of the useful
fields in the class are private, not protected. I also ran into another
architectural question, how does one pass a value (a-la constructor) into
one of these classes? If I'm going to use this to filter based on a
threshold, I'd need to pass that threshold in somehow.

On Wed, Aug 21, 2013 at 9:49 AM, John Vines <> wrote:

> There's no way to extend the ColumnQualietyFilter via configuration, but
> it sounds like you are on top of it. You just need to extend the class,
> possibly copy a bit of code, and change the equality check to a compareTo
> after converting the Strings to Doubles.
> On Wed, Aug 21, 2013 at 10:00 AM, Marc Reichman <
>> wrote:
>> I have some data stored in Accumulo with some scores stored as column
>> qualifiers (there was an older thread about this). I would like to find a
>> way to do thresholding when retrieving the data without retrieving it all
>> and then manually filtering out items below my threshold.
>> I know I can "fetch" column qualifiers which are exact.
>> I've seen the ColumnQualifierFilter, which I assume is what's in play
>> when I fetch qualifiers. Is there a reasonable pattern to extend this and
>> try to use it as a scan iterator so I can do things like "greater than" a
>> value which will be interpreted as a Double vs. the string equality going
>> on now?
>> Thanks,
>> Marc

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