[Zope-dev] Catalog improvements

Casey Duncan c.duncan@nlada.org
Tue, 27 Nov 2001 08:48:22 -0500


On Tuesday 20 November 2001 05:35 pm, Wolfram Kerber allegedly wrote:
> Hi,
>
> i'm currently working on a product that allows to attach relational
> information to zope-objects. It works quite well so far, but to further
> enhance it i need to make some changes to the Catalog. I could perhaps
> implement it as a separate product, but i strongly feel that those changes
> are best applied to the Catalog itself, as they are of general use (i
> think) and involve a lot of changes to the inner workings of the Catalog.
> In particular i need the following:
>
> - named/stored queries
> these are precompiled queries, so they can be executed without parsing and
> are easily cacheable
> i.e. similar to what is implemented in CMFTopic, but stored in the Catalog
> and a bit smarter
>
> - caching support
>
> - unions and intersections
> sub-queries (i.e. queries that are directed at a certain index) should be
> more flexibly combineable

I have some code that implements this in my CatalogQuery product. It creates 
a query object from a string. Presently these are not persistent, but they 
could easily be made to be to create precompiled queries.

code at: http://www.zope.org/Members/Kaivo/CatalogQuery

>
> I searched this mailing-list as well as zope.org to get an idea about what
> has already been discussed and requested, and there seems to be some
> interest in improving the Catalog. Some people even seem to have worked on
> this, perhaps they could give an update on this? Possibly i don't have to
> write everything from scratch...

I would be willing to help both in coding and getting the code put into the 
Zope core.

> I would have put this into a proposal, but there already are two proposals
> that deal with the features i want, one is dedicated to
> unions/intersections, the other (TopicIndexes) to performance issues (i
> dont't know what's the status of these though, especially the first one is
> rather old), and i don't want to hijack them without asking. As so often i
> will need to complete my current project first, but would then like to help
> in improving the Catalog for a more general use.

Possibly we need to rekindle discussion. I would suggest contacting the 
authors of those proposals to see how compatible your concepts are wth 
theirs. Perhaps a new proposal should be drafted with the new ideas and ty 
them back to the previous ones. If there is redundancy, that can be worked 
out.

>
> So, if there is interest, i would propose to collect some ideas and
> comments about how a better Catalog should look like, how it could be best
> implemented and how to organize this effort (with respect to the already
> existing proposals).

I am very interested in such a discussion. Let me know what I can do to help.

/---------------------------------------------------\
  Casey Duncan, Sr. Web Developer
  National Legal Aid and Defender Association
  c.duncan@nlada.org
\---------------------------------------------------/