On Fri, 1 Apr 2005 02:22:49 +0200, Quentin Mathé <[EMAIL PROTECTED]> wrote: > Le 31 mars 05, à 20:05, Yen-Ju Chen a écrit : > > > > Just a comment. > > Lucene is a general index and search engine. > > Applications are responsible for deciding > > which information should go into the index. > > Therefore, if an application put the metadata into > > the index, lucene can search on it. > > In the other word, lucene can search on meta-data > > and content. There is not difference to lucene. > > It all depends on how applications feed information to lucene. > > Thanks I was forgetting this point. > > However to have best performance possible it is better to avoid search > in content index when you just need to look at metadatas (with > Spotlight Apple has chosen to rely on two separate databases for > metadata and content index). > Well may be Lucene allows such keyed search but I don't remember about > such possibility. Do you know about such possibility ? > > hmm Beagle seems to put everything in a single database (both metadatas > and content index). > > I need to reread Lucene documentation :-)
Lucene do put everything in one database (metadata and content) because there is no difference between them. Content is just a very big metadata. All the data (metadata and content) is stored with keys (or field in lucene's terminology) just like NSDictionary. So you can specify which field to search. At least that's what I know for now. Haven't really work on the search/query part yet. The only thing to think about might be the speed. File system might be faster than lucene while searching in metadata. Pure speculation. The advantage to separate metadata and content might be that you can put all the metadata in memory, which will be much fast (real-time search). But lucene has different strategy for speeding. Yen-Ju > > Quentin. > > -- > Quentin Mathé > [EMAIL PROTECTED] > >
