What is wrong with the debtags database?

[Petter Reinholdtsen]

Can anyone explain what is going on here?  I try to figure out why
some packages are not showing up in golearn, and am completely lost.
I currently work in a sid chroot, to make sure the package lists are
as up to date as possible.

Here is a test run, showing that the stopmotion package is tagged with
all the right tags, yet fail to show up when I search for packages
with the field tag set:

root at minerva:~# chroot  /home/storage/chroot-sid/ bash -i
root at minerva:/# debtags search 'use::learning'|wc
    170    1326    9511
root at minerva:/# debtags search 'use::learning && role::program'|wc
    102     786    5250
root at minerva:/# debtags search 'use::learning && role::program && field::*'|wc
     38     270    1854
root at minerva:/# debtags search 'use::learning && role::program && !field::*'|wc
     64     516    3396
root at minerva:/# debtags search 'use::learning && role::program && !field::*'|grep stopmotion
stopmotion - program for creating stop motion animations
root at minerva:/# debtags search 'use::learning && role::program && field::*'|grep stopmotion
root at minerva:/# apt-cache show stopmotion
Package: stopmotion
Version: 0.6.2+git.1.10d2ea43-2
Installed-Size: 3949
Maintainer: Bjoern Erik Nilsen <bjoern.nilsen at bjoernen.com>
Architecture: i386
Depends: libc6 (>= 2.7), libgcc1 (>= 1:4.1.1), libinotifytools0 (>= 3.12), libqtcore4 (>= 4:4.7.0~beta1), libqtgui4 (>= 4:4.6.1), libsdl-image1.2 (>= 1.2.10), libsdl1.2debian (>= 1.2.11), libstdc++6 (>= 4.4.0), libtar0, libvorbisfile3 (>= 1.1.2), libx11-6, libxml2 (>= 2.7.4)
Recommends: vgrabbj, dvgrab, ffmpeg
Suggests: gimp
Description-en: program for creating stop motion animations                              
 You can create stop-motion animations with images grabbed                               
 from your favourite video device. You just sets stopmotion to                           
 use a grabber program which works with your device. It is also                          
 possible to do the same with video export; just plug in an                              
 encoder capable of doing video export from couple of images.                            
 .                                                                                       
 Stopmotion has a set of tools which helps you creating the                              
 movements smooth and precise.                                                           
Homepage: http://linuxstopmotion.sourceforge.net                                         
Description-md5: 7d6fd4e79094e054eb8301aeafa63d0e                                        
Tag: field::arts, hardware::camera, interface::x11, role::program,                       
 uitoolkit::qt, uitoolkit::sdl, use::learning,                                           
 works-with-format::oggtheora, works-with::image, works-with::video                      
Section: x11                                                                             
Priority: optional                                                                       
Filename: pool/main/s/stopmotion/stopmotion_0.6.2+git.1.10d2ea43-2_i386.deb              
Size: 2329182                                                                            
MD5sum: 199ac8f18250480f88916313cb64d07a                                                 
SHA1: cab6bd042cfc7b3101b956b376640eda24218eee                                           
SHA256: d8c2dd699477b806f7ce7674f33e9efd79ba63fbdc1b247a21e5b6974296d327                 
                                                                                         
root at minerva:/# 

apt-cache show that field::arts is set, role::program is set, and
use::learning is set, but the search for packages with these tags set
fail to match stopmotion.

The same problem affect other packages to, so stopmotion is just my
test package.

I've already executed 'apt-get update;update-apt-xapian-index' as root
to ensure everything should be up-to-date.

Are any of you able to explain what go wrong here?  Do I misunderstand
how this is supposed to work?

-- 
Happy hacking
Petter Reinholdtsen