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-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
