According to this page:
http://lucene.apache.org/core/old_versioned_docs/versions/2_9_1/queryparsersyntax.html
you can do searches like
title:"The Right Way" AND text:go
But when i do something like:
title:"The Right Way" OR title:"Home" I get no results even though I know there are pages with the title "Home".
How do I build a Lucene Query to do multiple ORs/ANDs for the same field ?
When debugging queries, I always use Luke. Luke lets you see exactly how Lucene interprets your query (as the ANDs and ORs are turned into SHOULDs and MUSTs).
If you print out Query queryParser.parse("title:\"The Right Way\" OR title:\"Home\"") by StandardAnalyzer, the result is Query is [title:"the right way" title:home]
Related
I would like to run a phrase search query on a Lucene 2.9 index and it doesn't return any results. The query is now stripped down to a very basic one but it still doesn't help. Where do I need to look at?
My failing search query is:
bodyText: "foo bar"
A query like the following works:
bodyText: (+foo +bar)
However the last query doesn't fit our purpose because I need a proper phrase search with words being in consecutive order.
I'm using Luke to test lucene queries.
Just to be sure, are you using the same analyzer when querying with Luke, as when you indexed your content? The default one for Luke (v 1.0.1) seems to be KeywordAnalyzer, so if you index your content with another analyzer, e.g. StandardAnalyzer and then try to query it with the KeywordAnalyzer it might not give the expected results.
I index content with StandardAnalyzer and phrase search in Luke works properly, providing that I use StandardAnalyzer when searching.
If the above is not the solution, you could also post your indexset and indexer configuration and the text you are indexing. This would allow recreating the issue.
I have a Cloudant database with a search index. In the search index I index the titles of my documents. For instance, search for 'rijkspersoneel':
http://wetten.cloudant.com/regelingen/_design/RegelingInfo/_search/regeling?q=title:rijkspersoneel
Returns 48 rows.
However, when I replace the 'o' with a ? wildcard:
http://wetten.cloudant.com/regelingen/_design/RegelingInfo/_search/regeling?q=title:rijkspers?neel
I get 0 results. Why is that? The Cloudant docs say that this should match 'rijkspersoneel' as well!
My previous answer was definitely mistaken. Internal wildcads do appear to be supported. Try:
title:rijkspe*on*
title rijksper?on*
Fairly sure what is happening here is an analysis issue. Fairly sure you are using a stemming analyzer. I'm not really all the familiar with cloudant and their implementation of this, but in Lucene, wildcard queries are not subject to the same analysis as term queries. I'm guessing that your analysis of this field includes a stemmer, in which case "rijkspersoneel" is actually indexed as "rijkspersone".
So, when you search for
rijkspersonee*
or
rijkper?oneel
Since the "el" is missing from the end in the indexed form, you find no matches. When just searching for rijkpersoneel it does get analyzed though, and you search for the stemmed form of the word, and will find matches.
Stemming and wildcards just don't get along.
i need to do not queries on my lucene index. Lucene currently allows not only when we have two or more terms in the query:
So I can do something like:
country:canada not sweden
but I can't run a query like:
country:not sweden
Could you please let me know if there is some efficient solution for this problem
Thanks
A very late reply, but it might be useful for somebody else later:
*:* AND NOT country:sweden
IF I'm not mistaken this should do a logical "AND" with all documents and the documents with a country that is different from "sweden".
Try with the following query in the search box:
NOT message:"warning"
message being the search field
Please check answer for similar question. The solution is to use MatchAllDocsQuery.
The short answer is that this is not possible using the standard Lucene.
Lucene does not allow NOT queries as a single term for the same reason it does not allow prefix queries - to perform either, the engine would have to look through each document to ascertain whether the document is/is not a hit. It has to look through each document because it cannot use the search term as the key to look up documents in the inverted index (used to store the indexed documents).
To take your case as an example:
To search for not sweden, the simplest (and possibly most efficient) approach would be to search for sweden and then "invert" the result set to return all documents that are not in that result set. Doing this would require finding all the required (ie. not in the result set) documents in the index, but without a key to look them up by. This would be done by iterating over the documents in the index - a task it is not optimised for, and hence speed would suffer.
If you really need this functionality, you could maintain your own list of items when indexing, so that a not sweden search becomes a sweden search using Lucene, followed by an inversion of the results using your set of items.
OK, I see what you are trying to do.
You can use it as a query refinement since there are no unary Boolean operators in Lucene. Despite the answers above, I believe this is a better and most forward approach (note the space before the wildcard):
&query= *&qf=-country:Canada
Using RavenDB to do a query on Lucene Index.
This query parses okay:
X:[[a]] AND Y:[[b]] AND Z:[[c]]
However this query gives me a parse exception:
X:[[a]] AND Y:[[b]] AND Z:[[c]] AND P:[[d]]
"Lucene.Net.QueryParsers.ParseException: Cannot parse '( AND )': Encountered \" \"AND"
I tried this on complexed index and simple reproduce cases and same result it seems once you go past three ands it blows up. Im using [[]] and not analyzed because i want exact matches (also sometimes values contain whitespace etc..) and from RavenDB I have veyr little control over the indexing.
Im wondering how I can rewrite the query to avoid the parse exception?
This is now fixed in the latest RavenDB builds. See this thread for more info.
This looks rather like a bug in Lucene's QueryParser, perhaps try reporting this in the user mailing list.
As a bypass, you could create a BooleanQuery manually and add the terms you want yourself. Since they are not analyzed, and the query doesn't look too complicated, you may be better off without the query-parser.
Is there any way to retrieve the match field/position for each keyword for each matching document from solr?
For example, if the document has title "Retrieving per keyword/field match position in Lucene Solr -- possible?" and the query is "solr keyword", I'd like to get, in addition to the doc-id (I normally only want the doc-id, not the full document), something that can tell me the matches are at:
solr:
title: 9
keyword:
title: 3
I'm pretty sure such info is computing during query execution (for phrase queries), but is it possible to return these to the application?
Thanks!
Debugging Relevance Issues in Search suggest using Solr analysis, which you can get to from the admin URL, using something like http://localhost:8983/solr/admin/analysis.jsp?highlight=on .
This highlights matching terms and gives their position.
AFAIK there is no way to do that directly, but you can use hit highlighting to implement it.