Hi,
Sending this mail again after I joined the sol-user group..Kindly find time
to help.
Thanks and Rgds,
Anil
---------- Forwarded message ----------
From: Anil Cherian <cherian.anil2...@gmail.com>
Date: Fri, Nov 13, 2009 at 3:48 PM
Subject: solr index-time boost... help required please
To: solr-user@lucene.apache.org, solr-...@lucene.apache.org
Hi,
I have been trying some BOOST functionality in SOLR. I learned how to do
query boosting on a date ie I wanted the latest approval_dt records to come
first in the results.
For that I copied and created a new dismax version called dismax boost in
solrconfig.xml
<requestHandler name="dismaxboost" class="solr.SearchHandler" >
<lst name="defaults">
<str name="defType">dismax</str>
<str name="echoParams">explicit</str>
<float name="tie">0.01</float>
<str name="qf">
text^0.5
</str>
<str name="pf">
text^0.2
</str>
<str name="bf">
recip(rord(approval_dt),1,1000,1000)^10.3 ord(popularity)^0.5
recip(rord(price),1,1000,1000)^0.3
</str>
<str name="fl">*</str>
<str name="mm">
2<-1 5<-2 6<90%
</str>
<int name="ps">100</int>
<str name="q.alt">*:*</str>
<!-- example highlighter config, enable per-query with hl=true -->
<str name="hl.fl">text features name</str>
<!-- for this field, we want no fragmenting, just highlighting -->
<str name="f.name.hl.fragsize">0</str>
<!-- instructs Solr to return the field itself if no query terms are
found -->
<str name="f.name.hl.alternateField">name</str>
<str name="f.text.hl.fragmenter">regex</str> <!-- defined below -->
</lst>
</requestHandler>
Then I just used the following query in SOLR:-
select?qt=dismaxboost&q=horticulture&version=2.2&start=0&rows=10&indent=on&bf=recip(rord(approval_dt),1,1000,1000)^110.0&fl=approval_dt
I got the results with latest dates of approval_dt first. I believe this was
query-time boosting.
Now I am trying *index-time *boosting to improve response time. So i created
an algorithm where I do the following:-
1. sort the records i get from database on approval_dt asc and increase the
boost value of the <field> element for approval_dt by 0.1 as i encounter
higer approval_dt records. If there is no approval_dt for a record, not
boost value for it. I made omitnorms=false in schema.xml for approval_dt
field. Now when I apply the same query nothing special happens ie I dont
even see the latest dates first.
I have some doubts like:-
1. Do we need to always use dismax query handler for BOOST ?
2. If we boost a doc or field in the xml should we again use the bf
parameter with a function to put the boost into effect while querying when
trying index-time boost also?
3. Also can you frame a query for me to see the latest approval_dt coming
first using the index-time boost approach.
4. Does bf function play any role in solrconfig.xml when we plan to use
index-time boost. My understanding is bf is used only for query-time boost.
5. Is it necessary to use bq in case of index time boost.
Could you please find some time to reply at your earliest convenience as i
am stuck on the index-time feature for some time and badly need to proceed.
Your help is much appreciated.
