Hello Mike; How about deleting by a compount term?
for example if I have a document with two fields srcId and dstId and I want to delete the document where srcId=1 and dstId=2 right now there exists a IndexWriter.deleteDocuments(Term t) but with that I can only delete lets say where srcId=something. I am sure there is a workaround but I could not find it. Best, On Jan 19, 2008 1:07 PM, Michael McCandless <[EMAIL PROTECTED]> wrote: > > Good question.... > > So far, this method has not been carried over to IndexWriter because > in general it's not really safe, since there's no way to get an > accurate docID from IndexWriter itself. > > You can't really "know" when IndexWriter does merges that compacts > deletes and thus changes docIDs. So, if you open a reader on the > side, get a docID you want to delete, and then go and ask IndexWriter > to delete that docID, you may in fact delete the wrong document. In > 2.3, where segment merges are now done with a background thread, it's > even worse, because a merge could complete and be committed, thus > changing docIDs, at any time... > > See complex discussion here: > > http://markmail.org/message/wxqel3gd6cmavk5a > > As of 2.3, the low level infrastructure was added to IndexWriter for > deleting by document ID, but this is not exposed publicly (this was a > side effect of LUCENE-1112). It's only used, internally, to delete a > document if an exception is hit while indexing it. In theory, you > could then subclass IndexWriter and tap into this infrastructure to > delete by docID, but, you're entering dangerous territory! > > Do you have a specific use case in mind here? I think we'd like to > make this option available someday in IndexWriter, but doing so now > (when there is no way to get a "reliable" docID) seems too dangerous... > > Mike > > Cam Bazz wrote: > > > Hello, > > > > How do I delete a specific document from an indexwriter? I > > understand there > > is deleteDocuments(term) which deletes all the documents matching > > the term. > > But what if I want to delete a document that has more then one term in > > specific. I can search the document with a boolean query, and then > > get the > > doc id. > > I know that doc ids are temporary, but can I not use it for delete? > > > > IndexReader has a delete by doc id method, but I am not sure how to > > use this > > when using an indexwriter. > > > > Best, > > C.B. > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > >
