: The question I'm trying to phrase is: Is there a way to make the rank of : SHOULD term conditional? : : In the example, I'm trying to express "If the term MEDICAL is found, the : term CAT ranks high; if the term ANIMAL is found, the term CAT ranks low."
except that there is an ambiguous situation here: what if a document contains both MEDICAL and ANIMAL ? you'll probably want a query something like this... (+MEDICAL -ANIMAL CAT^10) (+ANIMAL -MEDICAL CAT^0.1) (-ANIMAL -MEDICAL CAT) : According to Luke, I get two SHOULD clauses, each with a MUST and a : SHOULD. As I understood things, a SHOULD *term* merely affects the ranking : of the results, it doesn't affect what gets brought back. So I'm trying to : understand what a SHOULD *clause* does in this case. More importantly, what : does it logically mean to: "should have a must?" That's like saying I have : an optional mandatory term. not exactly ... Lucene queries "build up" result sets (hence you can't have a purely negative query) when a booleam query doesn't contain any MUST clauses, then at least one SHOULD clause must match a document for that document to make it into the result set. So when your outermost BooleanQuery contains two SHOULD clauses that means you need one or the other to match -- if both match, your score gets even higher. : Is it even possible to express this construct as a single expression or : data structure for the API: : 1. +( MEDICAL ANIMAL ) You must have either MEDICAL and/or ANIMAL. : 2. If MEDICAL present, then CAT ranks high, else, if ANIMAL present, : then CAT ranks low, otherwise the presence of the term CAT has no influence : on rank. ...ah, see when you elaborate on the details, it becoamse easier to spell out hte query structure... (+MEDICAL CAT^10) (+ANIMAL -MEDICAL CAT^0.1) in order for one of the main clauses to match, either MEDICAL or ANIMAL must match. if MEDICAL matches CAT scores high; we only care about ANIMAL matching if MEDICAL doesn't match -- in which case CAT ranks low. -Hoss --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
