Hi, Thanks for explanation. I almost expected that it has to do with" stored fields". It's easy to fix:
> ah ok, I know what you mean. We have to read out the stored field values > later. > A field can have multiple (stored) values (several > document.add(fieldable) invocations for one field). Further, we have the > problem that some field values are logically related to each other. Since > Lucene has no possibility to define relationships between documents, and offer > e.g. key-based, table-join-similar stuff, we took this approach as a kind of > approximation: > > Example document: (*fieldName: value1, value2, ..) > * personId: personId1, personId2, personId3, personIdN > * personName: personName1, personName2, personName3, personNameN > * personAge: personAge1, personAge2, personAge3, personAgeN > * tagId: tagId1, tagId2, tagId3, tagIdN > * tagLabel: tagLabel1, tagLabel2, tagLabel3, tagLabelN > * > > In the case there is e.g. no person age known for person 2, we have to insert > an > empty entry to ensure that all data for person 3 is in the third stored field > value > in this document: > > * personName: personName1, personName2, personName3, personNameN > * personAge: personAge1, EMPTYENTRY, personAge3, personAgeN > > since you can't create a numeric Field instance with a null entry (that would > be > wonderfull), we insert a string fieldable, so in this example the values for > 'personage1, personage3, and personageN are NumericFields, and > EMPTYENTRY is a standard string field with a zero-length string value "". This > results into exceptions when we sort against the personAge field. Then add those zero-length string fields with Field.Index.NO - they dnt have to be indexed. For your use case Store.YES is enough! > We also thinked about NaN or negative infinity as placeholder - but these are > only available at Float and Double. For Longs and Integers, only min_value and > max_value are offered. Further, we have to convert this value back into null > or > something empty, whereby the empty string value field integrates seamless as > it should (with respect to the exceptions ;) ) But maybe there is no other > possibility to take the max/min values? > > > > 2012/2/15 Uwe Schindler <u...@thetaphi.de>: > > Hi, > > > > This looks like an XY problem > (http://www.perlmonks.org/index.pl?node_id=542341). Maybe you should first > explain to us, why you need that. In Lucene fields have no "equal length" or > something like that, especially numeric fields are tokenized and contain of > several tokens separately indexed. So what do you mean with equal length? > Why must this "length" be identical? > > > > The only suggestion is to index a "fake" placeholder value (like -1, > > infinity, > NaN). If you only need it in the "stored" fields, just store it but don't > index it. > > > > Uwe > > > > ----- > > Uwe Schindler > > H.-H.-Meier-Allee 63, D-28213 Bremen > > http://www.thetaphi.de > > eMail: u...@thetaphi.de > > > > > >> -----Original Message----- > >> From: Christian Reuschling [mailto:christian.reuschl...@gmail.com] > >> Sent: Wednesday, February 15, 2012 12:58 PM > >> To: java-user > >> Subject: Empty numeric field > >> > >> Hi all, > >> > >> for some reason, we need empty numeric field values (to ensure that > >> the length of the field value list is constant). We tried to add an > >> empty String- Fieldable instead in the case a value is not present, > >> which seemed to work for searching. > >> Nevertheless, when we want to sort against this field, sadly we fall > >> into exceptions. > >> > >> Is there any possibility to store empty numeric fields into a > >> document/the index? > >> > >> Thanks > >> > >> Chris > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > >> For additional commands, e-mail: java-user-h...@lucene.apache.org > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > > For additional commands, e-mail: java-user-h...@lucene.apache.org > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
