# Use lucene query within ES-API **URL:** \ **Category:** Elasticsearch\ **Created:** [April 3, 2018, 1:00pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575 "2018-04-03T13:00:24Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Tobsucht](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/tobsucht/32/29265_2.png) [@Tobsucht](https://discuss.elastic.co/u/Tobsucht)\ **Post date:** [April 3, 2018, 1:00pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/1 "2018-04-03T13:00:25Z")
I'm building up complex queries within my application which involves that token streams are mapped to queries using a custom querybuilder sub-classed from "org.apache.lucene.util.Querybuilder". This produces lucene queries which, as far as i understand, cannot be directly used within the ES-API. I have written a small "query bridge" which maps lucene queries to the corresponding elastic-querybuilders, but is that really necessary? isn't there already a solution? ---
**Author:** ![Tobsucht](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/tobsucht/32/29265_2.png) [@Tobsucht](https://discuss.elastic.co/u/Tobsucht)\ **Post date:** [April 6, 2018, 10:07am UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/2 "2018-04-06T10:07:04Z")
Ok, I figured out that it might be better to move the query building process completely into ES. Actually I don't now whether I really need a custom querybuilder or not, so here is my scenario: I have a custom analyzer for the german language. Splitting up compound words results in the sub-terms having the same position in the tokenstream as the compound word. When using a "standard" querybuilder, this will result in a bool-query that puts every sub-term into a should clause. This might be problematic as the lucene score will be multiplied with a scoring value that represents "the business logic" for the current document. So what might happen is that a document, that matches maybe only one sub-term of the compound word will be placed at the top of the result set because it has a very high "business logic" scoring. Can this problem be solved with intelligent sub-queries or do I need to place my own querybuilder into ES? ---
**Author:** ![Tobsucht](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/tobsucht/32/29265_2.png) [@Tobsucht](https://discuss.elastic.co/u/Tobsucht)\ **Post date:** [April 9, 2018, 2:46pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/3 "2018-04-09T14:46:06Z")
I found out that the problem is that I'm using decompounding during search time, which is not a great idea. My analyzer is introducing informations about which terms are good candidates for fuzzy matching an which not. So I want to use this information in the querybuilder to decide when to use a simple Term- or FuzzyQuery. Is it possible to override the standard querybuilder which is used in MultiMatchQuery? If so, any example how this is done? ---
**Author:** ![jimczi](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jimczi/32/47985_2.png) [@jimczi](https://discuss.elastic.co/u/jimczi)\ **Post date:** [April 11, 2018, 12:40pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/4 "2018-04-11T12:40:08Z")
No it's not possible. It's a private class that applies the logic defined in the match query options and I don't think we should allow customizations at this level. You'll need to define your own query parser (that uses your custom query builder) in a plugin. You can also look at the custom field mapper option: [https://www.elastic.co/guide/en/elasticsearch/plugins/6.2/mapper.html](https://www.elastic.co/guide/en/elasticsearch/plugins/6.2/mapper.html) If you define your own field type you can override `MappedFieldType#termQuery` which is called by the query parsers to build a term query on the field. You cannot access the attributes from the token stream in this method so it depends on what you need to determine if a term is a good candidate for fuzzy matching or not (if you need more than the term itself). ---
**Author:** ![Tobsucht](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/tobsucht/32/29265_2.png) [@Tobsucht](https://discuss.elastic.co/u/Tobsucht)\ **Post date:** [April 12, 2018, 12:03pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/5 "2018-04-12T12:03:02Z")
The problem with using MappedFieldType is that I need more information than just the term. What I'm trying: for every token in a search query I'm doing a dictionary lookup, if its present =\> don't use fuzzing. As the analyzer is for the german language I'm also trying to decompose the token. If I can fully decompose it =\> don't use fuzzing. If it is partially decomposed, I will check the sub-terms whether they build the prefix of the token =\> use the prefix as prefixLength for the fuzzy query. Additional I don't want numbers to be fuzzed. So I think the only solution is to build my own query. As I only need to change a few lines compared to MatchQuery: I think it is not possible to just extend MatchQuery and its parser by overriding a few methods? ---
**Author:** ![jimczi](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jimczi/32/47985_2.png) [@jimczi](https://discuss.elastic.co/u/jimczi)\ **Post date:** [April 19, 2018, 10:35pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/6 "2018-04-19T22:35:43Z")
You can have a link to the dictionary in the `MappedFieldType` and performs the decomposition in `MappedFieldType#termQuery` and `MappedFieldType#fuzzyQuery` if you want but I agree that your use case is better suited for a `TokenFilter` or a query parser. Regarding the extensibility of the `MatchQuery` we could provide some extension point but you'd still need to write a plugin so this wouldn't save much. The logic in this query is quite simple so you can use it as a starting point for your query parser and add the option that you need freely. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [May 17, 2018, 10:35pm UTC](https://discuss.elastic.co/t/use-lucene-query-within-es-api/126575/7 "2018-05-17T22:35:55Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.