[Zope] Help with Search in Zope

[SAbel@microtest.ru]

[Oleg Broytmann]
> Developing special SQL-like language for ZCatalog? It is hard. What than?

[Chris McDonough]
> I think that it might be better to just
> use the callback to aggregate search results in interesting ways on a
> per-index basis.  For instance, if you specify three indexes in a query and
> specify a callback, the callback can do unions or intersections on the
> result sets returned from each index manually...

Wouldn't it be reasonable to look at Aaron Watters' kjbuckets extension?
(http://www.chordate.com/kjbuckets/)

It provides union, intersection and difference operations on set- and
dictionary-like datatypes.