Since version 3.1.1 UdmSearch has nested categories support.
Categories support is _alpha_ code. And there are almost no docs. :(

First you need to create tables for categories. For MySQL, use
create/mysql/categories.txt.

There is a categories editor written in PHP3. You can get it from
search.mnogo.ru (download page).

Well, categories are like old good tag feature, but nested. So you can have
one category inside another and so on.

The example categories set is at http://titan.izhcom.ru/~bar/categories.txt
And at http://titan.izhcom.ru/cgi-bin/search.cgi?cat=02 you can see example of
navigation through that categories.

Basic points:

- there are up to 5 nested levels;
- every level occupies 2 hex digits;
- parameter for setting category is 'path', which can be empty (means root
category) or up to 10 chars long (means deepest category).

You can also set up symlinks, e.g. categories that are actually links to
other categories. 'link' database field is used for that. In the symlink last
two characters should be @@. In example above Moto->BMV is a link to Auto->BMV.



