Our project is looking to transition to a new search engine to handle
our bibliographic databases (5.5M records of bibliographic article
metadata + 0.6M fulltext articles).  What we are looking for is
something easily tweakable, which offers fielded searches,
boolean/simple search logic, customizable relevance ranking, proximity,
highlighting, synonym/stemming matching.  Needs to run on a linux 64-bit
box.  The packages I am aware of are:

1. lucene/clucene/lucy
2. kinosearch
3. xapian
4. zebra
5. invenio

Am I missing any from the list?  Are any of these to be excluded based
on our requirements?  I'd like to hear experiences from people who are
using or have used these packages.

TIA

-- Alberto

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Dr. Alberto Accomazzi                  aaccomazzi(at)cfa harvard edu
NASA Astrophysics Data System                        ads.harvard.edu
Harvard-Smithsonian Center for Astrophysics      www.cfa.harvard.edu
60 Garden St, MS 67, Cambridge, MA 02138, USA
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