If you create two parallel indices (to use different parsing methods for instance), and always add and delete documents in parallel, will the document ID's always correspond in both indices? And could optimization destroy any such invariance?
-----Original Message----- From: Doug Cutting [mailto:[EMAIL PROTECTED] Sent: 17 November 2003 19:51 To: Lucene Users List Subject: Re: Which operations change document ids? Tate Avery wrote: > My first question is: should I steer clear of this all together? No, I think this is appropriate. > If not, I need to know which Lucene operations can cause document ids to change. > > I am assuming that the following can cause potential changes: > 1) Add document > 2) Optimize index > > What else could cause a document id to change? Nothing. And even these can only cause an id to change if there have been deletions. > Could delete provoke a doc id change? Not when you perform the delete. Later, when you add to or optimize the index, the ids for deleted documents are reclaimed. > And, I am assuming that the following DO NOT change the document id: > > 1) Query the index That is correct. Document ids never change with an instance of IndexReader. When you open a new index reader you should usually assume that ids have changed. Doug --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
