Itamar, Query rewrite replaces wildcards with terms available from the index. Usually that involves replacing a wildcard with a BooleanQuery that is an effective OR over the available terms while using a flat coordination factor, i.e. it does not matter how many of the available terms actually match a document, as long as at least one matches.
For the required query parts (AND like), Scorer.skipTo() is used, and that could well be the filter mechanism you are referring to; have a look at the javadocs of Scorer, and, if necessary, at the actual code of ConjunctionScorer. Regards, Paul Elschot Op Monday 07 April 2008 23:13:09 schreef Itamar Syn-Hershko: > Hi all, > > Can someone from the experts here explain why Lucene has to get a > "rewritten" query for the Searcher - so Phrase or Wildcards queries > have to rewrite themselves into a "primitive" query, that is then > passed to Lucene to look for? I'm probably not familiar too much with > the internals of Lucene, but I'd imagine that if you can inflate a > query using wildcards via xxxxQuery sub classing, you could as easily > (?) have some sort of Filter mechanism during the search, so that > Lucene retrieves the Position vectors for all the terms that pass > that filter, instead of retrieving only the position data for > deterministic terms (with no wildcards etc.). If that was possible to > do somehow, it could greatly increase the searchability of Lucene > indices by using RegEx (without re-writing and getting the dreaded > MaxClauseCount error) and similar. > > Would love to hear some insights on this one. > > Itamar. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
