Re: problem with formulating a negative query
Hi, Chris Hostetter wrote: AND, OR, and NOT are just syntactic-sugar for modifying the MUST, MUST_NOT, and SHOULD. The default op of OR only affects the first clause of your query (R) because it doesn't have any modifiers -- Thanks for pointing that out! -Sascha the second clause has that NOT modifier so your query is effectivley... topic:R -topic:[* TO *] ...which by definition can't match anything. -Hoss
Re: problem with formulating a negative query
: thanks for your explanations. But why are all docs being *removed* from the : set of all docs that contain R in their topic field? This would correspond to : a boolean AND and would stand in conflict with the clause q.op=OR. This seems : a bit strange to me. Erick's explanation might have been a tad missleading ... it's not an ordered operation, AND, OR, and NOT are just syntactic-sugar for modifying the MUST, MUST_NOT, and SHOULD. The default op of OR only affects the first clause of your query (R) because it doesn't have any modifiers -- the second clause has that NOT modifier so your query is effectivley... topic:R -topic:[* TO *] ...which by definition can't match anything. -Hoss
Re: problem with formulating a negative query
Hi Erick, thanks for your explanations. But why are all docs being *removed* from the set of all docs that contain R in their topic field? This would correspond to a boolean AND and would stand in conflict with the clause q.op=OR. This seems a bit strange to me. Furthermore, Smiley Pugh stated in their Solr 1.4 book on pg. 102 that adding the a subexpression containing the negative query (-[* TO *]) and the match-all-docs clause (*:*) is only a workaround. Why is this workaround necessary at all? Best, Sascha Erick Erickson wrote: This may help: http://lucene.apache.org/java/2_4_0/queryparsersyntax.html#Boolean%20operators But the clause you specified translates roughly as find all the documents that contain R, then remove any of them that match * TO *. * TO * contains all the documents with R, so everything you just matched is removed from your results. HTH Erick On Tue, Jun 29, 2010 at 12:40 PM, Sascha Szottsz...@zib.de wrote: Hi Ahmet, it works, thanks a lot! To be true I have no idea what's the problem with defType=luceneq.op=ORdf=topicq=R NOT [* TO *] -Sascha Ahmet Arslan wrote: I have a (multi-valued) field topic in my index which does not need to exist in every document. Now, I'm struggling with formulating a query that returns all documents that either have no topic field at all *or* whose topic field value is R. Does this work? defType=luceneq.op=ORq=topic:R (+*:* -topic:[* TO *])
problem with formulating a negative query
Hi folks,
I have a (multi-valued) field topic in my index which does not need to
exist in every document. Now, I'm struggling with formulating a query
that returns all documents that either have no topic field at all *or*
whose topic field value is R.
Unfortunately, the query
/select?q={!lucene q.op=OR df=topic}(R NOT [* TO *])
does not return any docs even though there are documents in my index
that fulfil the specified condition as you can deduce from the queries
listed below:
/select?q=topic:R returns 0 docs
/select?q=-topic:[* TO *] returns 0 docs
Appending the query with debugQuery=true returns:
str name=rawquerystring{!lucene q.op=OR df=topic}(R NOT [* TO *])/str
str name=querystring{!lucene q.op=OR df=topic}(R NOT [* TO *])/str
str name=parsedquerytopic:R -topic:[* TO *]/str
str name=parsedquery_toStringtopic:R -topic:[* TO *]/str
Does anybody have a clue of what is wrong here?
Thanks in advance,
Sascha
Re: problem with formulating a negative query
I have a (multi-valued) field topic in my index which does not need to exist in every document. Now, I'm struggling with formulating a query that returns all documents that either have no topic field at all *or* whose topic field value is R. Does this work? defType=luceneq.op=ORq=topic:R (+*:* -topic:[* TO *])
Re: problem with formulating a negative query
This may help: http://lucene.apache.org/java/2_4_0/queryparsersyntax.html#Boolean%20operators But the clause you specified translates roughly as find all the documents that contain R, then remove any of them that match * TO *. * TO * contains all the documents with R, so everything you just matched is removed from your results. HTH Erick On Tue, Jun 29, 2010 at 12:40 PM, Sascha Szott sz...@zib.de wrote: Hi Ahmet, it works, thanks a lot! To be true I have no idea what's the problem with defType=luceneq.op=ORdf=topicq=R NOT [* TO *] -Sascha Ahmet Arslan wrote: I have a (multi-valued) field topic in my index which does not need to exist in every document. Now, I'm struggling with formulating a query that returns all documents that either have no topic field at all *or* whose topic field value is R. Does this work? defType=luceneq.op=ORq=topic:R (+*:* -topic:[* TO *])
