That can be specified with a pull-down menu should not be added to a are better addedĭirectly through the query API. All others, such as date ranges, keywords, etc. In a query form, fields which are general text should use the query.Should be consistently program-generated. Program-generated values, like dates, keywords, etc., If a field's values are generated programmaticallyīy the application, then so should query clauses for this field.Īn analyzer, which the query parser uses, is designed to convert human-entered Untokenized fields are best added directly to queries, and not.Parser is designed for human-entered text, not for program-generated Your queries directly with the query API. Parsing it with the query parser then you should seriously consider building If you are programmatically generating a query string and then.Version of Lucene, please consult the copy ofĭocs/queryparsersyntax.html that was distributedīefore choosing to use the provided Query Parser, please consider the following: Generally, the query parser syntax may change from Interprets a string into a Lucene Query using JavaCC. ![]() Language through the Query Parser, a lexer which Queries through its API, it also provides a rich query Here's a simple example: String str = "foo bar" īq.add(new TermQuery(new Term("id", id), Lucene provides the ability to create your own Use the BooleanQuery object to join and nest queries. Besides, there are some queries which are not possible to construct by parsing. Lucene queries can also be constructed programmatically. Query q = new QueryParser(Version.LUCENE_CURRENT, "title", analyzer).parse(querystr) String querystr = args.length > 0 ? args : "lucene" Queries can be parsed by constructing a QueryParser object and invoking the parse() method. The query syntax has not changed significantly since Lucene 1.3 (it is now 3.5.0). The official docs for the query parser syntax are here: You should carefully examine explain output to determine the appropriate boost weights. The higher the boost factor, the more relevant the term will be, and therefore the higher the corresponding document scores.Ī typical boosting technique is assigning higher boosts to title matches than to body content matches: (title:foo OR title:bar)^1.5 (body:foo OR body:bar) Query-time boosts allow one to specify which terms/clauses are "more important". Solr's built-in field types are very convenient for performing range queries on numbers without requiring padding. Range Queries can be inclusive or exclusive of the upper and lower bounds. Range Queries allow one to match documents whose field(s) values are between the lower and upper bound specified by the Range Query. Solr DisMax and eDisMax query parsers can add phrase proximity matches to a user query. The trade-off, is that the proximity query is slower to perform and requires more CPU. Whilst both queries are effectively equivalent with respect to the documents that are returned, the proximity query assigns a higher score to documents for which the terms foo and bar are closer together. Note that for proximity searches, exact matches are proximity zero, and word transpositions (bar foo) are proximity 1.Ī query such as "foo bar"~10000000 is an interesting alternative to foo AND bar. Search for "foo bar" within 4 words from each other. Lucene supports finding words are a within a specific distance away. Note that Lucene doesn't support using a * symbol as the first character of a search. ![]() Search for any word that starts with "foo" and ends with bar in the title field. Search for any word that starts with "foo" in the title field. Search for word "foo" and not "bar" in the title field. (title:"foo bar" AND body:"quick fox") OR title:fox Search for either the phrase "foo bar" in the title field AND the phrase "quick fox" in the body field, or the word "fox" in the title field. Search for phrase "foo bar" in the title field AND the phrase "quick fox" in the body field. Search for phrase "foo bar" in the title field. ![]() Search for word "foo" in the title field. Here are some query examples demonstrating the query syntax. Lucene has a custom query syntax for querying its indexes.
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