Xapian discuss - Mar 2006 - Giving titles extra weights and searching with titles

What's the best technique for giving the terms in, say, a document
title more weight than the terms? Do I simply use the third "wdfinc
"parameter to Xapian::Document::add_posting to give it more weight?

Secondly, if I wanted to make it possible to search just within a
title, would I also need to store the same of terms prefixed with, say
TITLE: to do that?

Paul

On Wed, Mar 29, 2006 at 11:12:57PM +0100, Paul Dixon wrote:
> What's the best technique for giving the terms in, say, a document
> title more weight than the terms? Do I simply use the third "wdfinc
> "parameter to Xapian::Document::add_posting to give it more weight?
That will do it, yes.
> Secondly, if I wanted to make it possible to search just within a
> title, would I also need to store the same of terms prefixed with, say
> TITLE: to do that?
I'd be inclined to generate terms prefixed with "S", and then use
a
prefix map to the QueryParser to map "title:" in a query to
"S".

qp.add_prefix("title", "S")

if you're using it directly, or something like:

$setmap{prefix,title,S}

in an omegascript template.

J

-- 
/--------------------------------------------------------------------------\
  James Aylett                                                  xapian.org
  james@tartarus.org                               uncertaintydivision.org

On Wed, Mar 29, 2006 at 11:12:57PM +0100, Paul Dixon
wrote:
> What's the best technique for giving the terms in, say, a document
> title more weight than the terms? Do I simply use the third "wdfinc
> "parameter to Xapian::Document::add_posting to give it more weight?
Yes.
> Secondly, if I wanted to make it possible to search just within a
> title, would I also need to store the same of terms prefixed with, say
> TITLE: to do that?
Yes.  The conventional prefix for subject or title is "S" - the
advantage of using this is compatibility with other Xapian databases
built by other applications.  For more information, see termprefixes.txt
in the omega documentation:

http://svn.xapian.org/*checkout*/trunk/xapian-applications/omega/docs/termprefixes.txt

Cheers,
    Olly