[Xapian-discuss] Prioritizing xapian search results

[Olly Betts]

On Sun, Jan 29, 2006 at 05:45:36PM -0500, info at bannershift.com wrote:
> It is possible somehow to give higher priority to recent document. For 
> example, when adding new document to the database, I will add a term 
> that specifies date of the document. During the search, the date of the 
> document is taken into account in the algorithm that calculates 
> document relevancy.

This is what the match bias functor was originally intended to be for.
You might find it useful in its current state:

http://www.xapian.org/docs/apidoc/html/classXapian_1_1Enquire.html#a13

> In another project I am working on, I would like to limit number of 
> pages returned from the same site. Basically I need to limit number of 
> results that could have the same term that specifies site id. I would 
> like to know if this could be done.

You can can eliminate all but one page from the same site by adding
the sitename as a value and using Enquire::set_collapse_key:

http://www.xapian.org/docs/apidoc/html/classXapian_1_1Enquire.html#a5

I think it should be possible to enhance the collapse key to keep up to
N matches (where N can be specified).  I'll investigate when I get a
chance.

Cheers,
    Olly