Several things in this thread should be clarified (note: order of quotations munged for clarity)...
: I had read this page. But I'm not using the "NOT" operator, I'm using the : "-" operator. I'm assuming there is a subtle difference between them in : that NOT qualifies something else, hence needs 2 terms. Isn't the "-" : operator supposed to be a complement to the "+" operator, ie. excludes : something rather than requiring it ? "The NOT operator" and "the - operator" are in fact the same thing ... the duplicate syntax comes from Lucene trying to appease people that want boolean style operator synta (AND/OR/NOT) even though the query parser is not a boolean syntax. : > Have you seen this page? : > http://lucene.apache.org/java/docs/queryparsersyntax.html : > : > From that page: : > Note: The NOT operator cannot be used with just one term. For example, : > the following search will return no results: : > NOT "jakarta apache" In Solr, the query parser can in fact support purely negative queries, by internally transforming the query, this is noted on the Solr query syntax wiki... http://wiki.apache.org/solr/SolrQuerySyntax : > > field_name:(-null) "null" is not a special keyword, if you look at the debugging output when doing that query you'll see that it is the same as: -field_name:null ... which is a search for all docs containing the string "null" in the field "field_name". : The *:* (star colon star) means "all records". The trick is to use (*:* AND : -field:[* TO *]). It's silly, but there it is. as i mentioned, you can do pure wildcard queries now, so a simple search for -field_name:[* TO *] will find all docs that have no indexed values for that field at all. : A performance note: we switched from empty fields to fields with a standard : 'empty' value. This way we don't have to do a range check to find records : with empty fields. Your milage may vary depending on how many docs you have with "no value" ... this also issn't practical when dealing with numeric, boolean, or date based fields. (and depending on how much churn there is in your index, the filterCache can probably make the difference negliable on average anyway). -Hoss
