One possibility to consider - if you really need documents with specifically empty or non-defined values (if that's not an oxymoron :)), and you have control over the values you send into the indexing, you could set a special value that means 'no value'. We've done that in a similar vein, using something like '@@EMPTY@@' for a given field, meaning that the original document didn't actually have a value for that field. I.E. it is something very unlikely to be a 'real' value - and then we can easily select on documents by querying for the field:@@EMPTY@@ instead of the negated form of the select... However, we haven't considered things like what it does to index size. It's relatively rare for us (that there not be a value), so our 'gut feel' is that it's not impacting the indexes very much size-wise or performance-wise.
Bob Sandiford | Lead Software Engineer | SirsiDynix P: 800.288.8020 X6943 | bob.sandif...@sirsidynix.com www.sirsidynix.com > -----Original Message----- > From: Viswa S [mailto:svis...@hotmail.com] > Sent: Saturday, November 20, 2010 5:38 PM > To: solr-user@lucene.apache.org > Subject: RE: Empty value/string matching > > > Erick, > Thanks for the quick response. The output i showed is on a test > instance i created to simulate this issue. I intentionally tried to > create documents with no values by creating xml nodes with "<field > name="fieldName"></field>", but having values in the other fields in a > document. > Are you saying that there is no way have a field with no value?, with > text fields they seem to make sense than for string?. > You are right on fieldName:[* TO *] results, which basically returned > all the documents which included the couple of documents in question. > -Viswa > > Date: Sat, 20 Nov 2010 17:20:53 -0500 > > Subject: Re: Empty value/string matching > > From: erickerick...@gmail.com > > To: solr-user@lucene.apache.org > > > > I don't think that's correct. The documents wouldn't be showing > > up in the facets if they had no value for the field. So I think > you're > > being mislead by the printout from the faceting. Perhaps you > > have unprintable characters in there or some such. Certainly the > > name:" " is actually a value, admittedly just a space. As for the > > other, I suspect something similar. > > > > What results do you get back when you just search for > > FieldName:[* TO *]? I'm betting you get all the docs back, > > but I've been very wrong before. > > > > Best > > Erick > > > > On Sat, Nov 20, 2010 at 5:02 PM, Viswa S <svis...@hotmail.com> wrote: > > > > > > > > Yes I do have a couple of documents with no values and one with an > empty > > > string. Find below the output of a facet on the fieldName. > > > ThanksViswa > > > > > > > > > <int name="">2</int><int name="CASTIGO.430">2</int><int > > > name="GDOGPRODY.424">2</int><int name="QMAGIC.412">2</int><int > name=" > > > ">1</int> > > > > Date: Sat, 20 Nov 2010 15:29:06 -0500 > > > > Subject: Re: Empty value/string matching > > > > From: erickerick...@gmail.com > > > > To: solr-user@lucene.apache.org > > > > > > > > Are you absolutely sure your documents really don't have any > values for > > > > "FieldName"? Because your results are perfectly correct if every > doc has > > > a > > > > value for "FieldName". > > > > > > > > Or are you saying there no such field as "FieldName"? > > > > > > > > Best > > > > Erick > > > > > > > > On Sat, Nov 20, 2010 at 3:12 PM, Viswa S <svis...@hotmail.com> > wrote: > > > > > > > > > > > > > > Folks,Am trying to query documents which have no values > present, I have > > > > > used the following constructs and it doesn't seem to work on > the solr > > > dev > > > > > tip (as of 09/22) or the 1.4 builds.1. (*:* AND -FieldName[* TO > *]) - > > > > > returns no documents, parsedquery was "+MatchAllDocsQuery(*:*) > > > -FieldName:[* > > > > > TO *]"2. -FieldName:[* TO *] - returns no documents, > parsedquery was > > > > > "-FieldName:[* TO *]"3. FieldName:"" - returns no documents, > > > parsedquery was > > > > > empty (<str name="parsedquery"/>)The field is type string, > using the > > > > > LuceneQParser, I have also tried to see if "FieldName:[* TO *]" > if the > > > > > documents with no terms are ignored and didn't seem to be the > case, the > > > > > result set was everything.Any help would be appreciated.-Viswa > > > > > > > > > > > >
