lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Andres de la Peña <adelap...@stratio.com>
Subject Re: Filter strategy in Lucene 6.0
Date Tue, 02 Aug 2016 17:07:30 GMT
Thanks Adrien, this is very helpful.

I have just read your blog post about this
<https://www.elastic.co/blog/better-query-execution-coming-elasticsearch-2-0>,
the two-phase iteration is really cool!

2016-07-31 20:17 GMT+01:00 Adrien Grand <jpountz@gmail.com>:

> Lucene 5.0 introduced two-phase iteration
> (see Scorer.twoPhaseIterator()) as a way to tackle slow queries. In short,
> queries can be split into a fast approximation and a slower confirmation
> and Lucene makes sure to reach agreement between the different
> approximations of a BooleanQuery before checking the confirmations.
>
> Both approximations and confirmations have an API that allows them to
> expose a "cost" and the least costly components are always evaluated before
> the most costly ones. So the filter strategy is not useful anymore, every
> decision is made based on these cost APIs.
>
>
> Le ven. 22 juil. 2016 à 15:32, Andres de la Peña <adelapena@stratio.com> a
> écrit :
>
> > Hi all,
> >
> > Suppose that we have a boolean query composed by two filtering queries,
> > where one of them is fast and the other is slow:
> >
> > BooleanQuery.Builder builder = new BooleanQuery.Builder();
> > builder.add(fastQuery, FILTER);
> > builder.add(slowQuery, FILTER);
> > Query query = builder.build();
> >
> >
> > How is the intersection between the two sub-queries calculated? Is the
> > order in which they are added to the boolean query relevant? Is there
> > something we could do to take advantage of my knowledge about the
> expected
> > performance of the sub-queries?
> >
> > Prior to Lucene 6.0 there was a FilteredQuery.FilterStrategy providing
> some
> > control about this. Is there something analogous in Lucene 6.0?
> >
> > Thanks in advance,
> >
> > --
> > Andrés de la Peña
> >
> > Vía de las dos Castillas, 33, Ática 4, 3ª Planta
> > 28224 Pozuelo de Alarcón, Madrid
> > Tel: +34 91 828 6473 // www.stratio.com // *@stratiobd
> > <https://twitter.com/StratioBD>*
> >
>



-- 
Andrés de la Peña

Vía de las dos Castillas, 33, Ática 4, 3ª Planta
28224 Pozuelo de Alarcón, Madrid
Tel: +34 91 828 6473 // www.stratio.com // *@stratiobd
<https://twitter.com/StratioBD>*

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message