> Using Solr 1.4 I wanted to construct a query that returns > documents that > have a particular field value or are missing the field. The > first thing I > came up with was: > > field1:particularvalue OR -field1:[* TO *] > > It turns out the -field1:[* TO *] was being ignored. If > particularvalue > wasn't found, for instance, it returned 0 hits. > > Well after a lot of experimentation I found a query that > works as expected: > > field1:particularvalue OR (*:* AND -field1:[* TO *]) > > It seems like a hack though. Am I approaching this the > wrong way? What's the > recommended way for doing this type of search?
What you have found/done is correct way of doing this. "When dealing with Lucene people are strongly encouraged to think in terms of MUST, MUST_NOT and SHOULD (which are represented in the query parser as the prefixes "+", "-" and the default) instead of in terms of AND, OR, and NOT ... Lucene's Boolean Queries (and thus Lucene's QueryParser) is not a strict Boolean Logic system, so it's best not to try and think of it like one." [1] [1] http://search-lucene.com/m/wEUvc10TfyQ/
