[Zope-CMF] Improvement of CMFTopic?

Jeffrey Shell jeffrey@Digicool.com
Thu, 17 May 2001 10:54:38 -0400


On Thursday, May 17, 2001, at 01:52  AM, marc lindahl wrote:

> I was playing around with CMFTopic, trying to figure out how best 
> to utilize
> it, and it occurred to me that:
>
> Since 'list criteria' seems to do an OR match of things on the 
> list, perhaps
> either there could be a way to have an AND list to refine a 
> search, or, be
> able to add multiple instances of the same search field id which would
> AND...
>
> This to avoid having to build a pile of subtopics just to get an AND
> search...
>
> This in the context of the 'subject' field, used as a 
> multiple-select list
> as outlined in the DublinCore docs (and applicable to other 
> similar field).
>
> Allowing multiple instances of the same id shouldn't be to hard 
> (something
> to do with listAvailableFields?)... adding a radio button set to list
> criterion to tag them as AND or OR would be more of a pain 
> (another property
> to look after?)

You can't do this currently on a per-query basis.  Remember (or 
note) that CMF Topic is just a static query builder, and is reliant 
solely on the queries that can be passed to Catalog.  And, for 
better or worse, Catalog has a pretty weak query language at 
present.  Beyond the ugly range operator, there are not many ways 
you can customize a query - they're all dependant on the indexes.

In Zope 2.4, catalogs will have a new feature known as *drop-in 
indexes*.  This is to facilitate the creation of new index types, 
and allow more configuration options on a per-index basis.  I've 
been told that one of these configuration options will be the 
ability to set whether results from a Keyword index should be AND 
or OR'd.

Drop in indexes should allow us to make CMF Topic an actual index 
in the future, which will make it very fast at read time.  This 
feature is still a few revisions away.

Jeffrey P Shell, jeffrey@Digicool.com
http://www.digicool.com/ | http://www.zope.org/