If you use LogMergePolicy ie. do merges in order you could use the absolute docID as a relative age value. Smaller docIDs mean younger documents. Maybe this works for you?
simon On Wed, Nov 30, 2011 at 9:08 PM, Zhang, Lisheng <lisheng.zh...@broadvision.com> wrote: > Thanks very much for your helps! I got the point, only problem is that > I cannot afford to to use FieldCache because in our app we have many > lucene index data folders, is there another simple way? > > Thanks again, Lisheng > > -----Original Message----- > From: Simon Willnauer [mailto:simon.willna...@googlemail.com] > Sent: Wednesday, November 30, 2011 11:40 AM > To: java-user@lucene.apache.org > Subject: Re: Boost more recent document > > > On Wed, Nov 30, 2011 at 6:59 PM, Zhang, Lisheng > <lisheng.zh...@broadvision.com> wrote: >> Hi, >> >> We need to boost document which is more recent (each doc has time stamp >> attribute). It seems that >> we cannot use doc boost at index time because it will be condensed into one >> byte (cannot differentiate >> 365 days), so we may use payload (save time stamp as payload) to boost at >> search time. >> >> In our app we let user enter query at browser and use QueryParser to >> generate query, the query can >> be different types (TermQuery, BooleanQuery, WildcardQuery, ...), then it >> seems we need to create >> each customized query class similar to PayloadTermQuery, is there another >> simpler way? > > you can simply index your timestamp (untokenzied) and wrap your query > in a CustomScoreQuery. This query accepts your user query and a > ValueSource. During search CustomScoreQuery calls your valuesource for > each document that the user query scores and multiplies the result of > the ValueSource into the score. Inside your valuesource you can simply > get the timestamps from the FieldCache and calculate your custom > boost... > > hope that helps > > simon >> >> Thanks very much for helps, Lisheng > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
