Xapian discuss - Jul 2011 - return values in groups - price range groups

Hi colleagues,


 

I have a simple
product database indexed with Xapian. Amazing free tool, thanks you
developer(s)!

 

I need to
have a way to return prices of products in groups, say I have prod prices:

1.01

1.03

 

10.01

 

250.44

260.33

 

I need to
get it to return something like: 

Group 1 1.01 ? 1.03

Group 2 10.01

etc.

 

Maybe there
is something build-in Xapian that can do this? I re-read the docs, but didn?t
see it, still I thought it?s worth asking.

 

Any tips
how to go about this developing myself to minimise db load? 


 

 

Thank you
guys! 

Andy

On Thu, Jul 07, 2011 at 07:50:43AM +0300, Internets Datoram
wrote:
> I need to
> have a way to return prices of products in groups, say I have prod prices:
[...]
> I need to
> get it to return something like: 
> 
> Group 1 > 1.01 ? 1.03
> 
> Group 2 > 10.01
> 
> etc.
> 
> Maybe there
> is something build-in Xapian that can do this? I re-read the docs, but
didn?t
> see it, still I thought it?s worth asking.
You can use a MatchSpy to extract all the prices which occur in the
matched documents:

http://xapian.org/docs/facets

Although it doesn't say so there, the values can be a more continuous
quantity like price, as well as discrete things like colour or product
type.

There's no support for building "buckets" by price in the released
version of this feature, so you'd have to implement that part.

There was something to do this in the original implementation, but it
didn't seem to do what users actually wanted, and the API was rather
complex, but it is still on the branch if you want to look - here's the
API header for it (the NumericRanges stuff towards the end is what
you're wanting):

http://trac.xapian.org/browser/branches/matchspy/xapian-core/include/xapian/matchspy.h

Cheers,
    Olly