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From David Medinets <>
Subject Re: Filtering on column qualifier
Date Thu, 22 Aug 2013 16:16:46 GMT
Have you thought of writing a filter class that takes some bit of groovy
for execution inside the accept method, depending on how efficient you need
to be and how changeable your constraints are.

On Thu, Aug 22, 2013 at 10:19 AM, Marc Reichman <> wrote:

> 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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