lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Grant Ingersoll <gsing...@apache.org>
Subject Re: access payload from HitCollector.collect()
Date Mon, 22 Mar 2010 15:40:16 GMT

On Mar 22, 2010, at 8:56 AM, prasenjit mukherjee wrote:

> I am trying to implement oracle's aggregation like SQL's  ( e.g.
> SUM(col3) where col1='foo' and col2='bar' ) using lucene's payload
> feature.
> 
> I can add the integer_value ( of col3 ) as a payload to my searchable
> fields ( col1 and col2 ). I can probably extend the
> DefaultSImilarity's scorePayload() to compute the aggregated value.
> But was wondering if I can access the payload values from
> HitColelctor.collect() as I really dont need to do any score
> computation. I just want the sum of col3's values  for all matching
> documents.
> 
> What is a good approach to achieve the above? The use case is slightly
> different and more like RDBMS, but still ( methinks )  lucene seems to
> the best tool available to do these kind of computation in a large
> scale.

See the SpanQuery class and the associated Spans class, which should provide you access to
the matching docs, w/o scoring, as well as the payload values.

-Grant
---------------------------------------------------------------------
To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-user-help@lucene.apache.org


Mime
View raw message