# Hyphenation decompounder token filter seems to ignore the \`only\_longest\_match\` option
**URL:** https://discuss.elastic.co/t/hyphenation-decompounder-token-filter-seems-to-ignore-the-only-longest-match-option/294047
**Category:** Elasticsearch
**Created:** [January 11, 2022, 2:31pm UTC](https://discuss.elastic.co/t/hyphenation-decompounder-token-filter-seems-to-ignore-the-only-longest-match-option/294047 "2022-01-11T14:31:23Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Jelena\_Malinovic](https://discuss.elastic.co/u/Jelena_Malinovic)
#### Post date: [January 11, 2022, 2:31pm UTC](https://discuss.elastic.co/t/hyphenation-decompounder-token-filter-seems-to-ignore-the-only-longest-match-option/294047/1 "2022-01-11T14:31:23Z")
Hi everyone,
We are trying to improve searches on our website which include compounds words. For that purpose, we are using the token filter `hyphenation_decompounder`. During testing, we found out that `only_longest_match` option doesn't work as intended.
Here is the output after running the `_analyze` API. Of course, we used a much longer list of words, but I have singled out here only words relevant to my example.
```auto
GET _analyze
{
"tokenizer": "whitespace",
"filter": [
{
"type": "hyphenation_decompounder",
"hyphenation_patterns_path" : "german_hyphenation_patterns.xml",
"only_longest_match": true,
"max_subword_size": 22,
"word_list": [
"kinder",
"wagen",
"gen"
]
}
],
"text": "kinderwagen"
}
```
The result is:
```auto
{
"tokens" : [
{
"token" : "kinderwagen",
"start_offset" : 0,
"end_offset" : 11,
"type" : "word",
"position" : 0
},
{
"token" : "kinder",
"start_offset" : 0,
"end_offset" : 11,
"type" : "word",
"position" : 0
},
{
"token" : "wagen",
"start_offset" : 0,
"end_offset" : 11,
"type" : "word",
"position" : 0
},
{
"token" : "gen",
"start_offset" : 0,
"end_offset" : 11,
"type" : "word",
"position" : 0
}
]
}
```
It seems like "gen" is still considered as a relevant token for this case, although a words lists contain "wagen" and we set `only_longest_match` to true.
Any ideas why this happens? Are we missing something here, in the token filter configuration? Can this be a bug?
Any help is appreciated.
---
### Author:  [@Tomo\_M](https://discuss.elastic.co/u/Tomo_M)
#### Post date: [January 11, 2022, 3:26pm UTC](https://discuss.elastic.co/t/hyphenation-decompounder-token-filter-seems-to-ignore-the-only-longest-match-option/294047/2 "2022-01-11T15:26:18Z")
Hi,
I found a relevant discussion. Unfortunately, it seems a known Lucene behaviour. If so, the name 'only\_longest\_match' is a bit confusing but consistent with Lucene onlyLongedtMatch flag.
> [@Compound word token filter: only\_longest\_match doesn't work as expected in some scenarios](https://discuss.elastic.co/t/compound-word-token-filter-only-longest-match-doesnt-work-as-expected-in-some-scenarios/195470/2):
>
> The only\_longest\_match option may not quite work how you think it does. [This Lucene issue comment](https://issues.apache.org/jira/browse/LUCENE-8183?focusedCommentId=16374886&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-16374886) has details on how it works: The onlyLongestMatch flag currently affects whether all matches or only the longest match should be returned per start character (in DictionaryCompoundWordTokenFilter) or per hyphenation start point (in HyphenationCompoundWordTokenFilter). Example: Dictionary "Schaft", "Wirt", "Wirtschaft", "Wissen", "Wissenschaft" for input "Wirtschaftswissenschaft" will retu…
---
### Author:  [@Jelena\_Malinovic](https://discuss.elastic.co/u/Jelena_Malinovic)
#### Post date: [January 12, 2022, 5:12pm UTC](https://discuss.elastic.co/t/hyphenation-decompounder-token-filter-seems-to-ignore-the-only-longest-match-option/294047/3 "2022-01-12T17:12:53Z")
Thanks for clarifying this!
---
### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [February 9, 2022, 5:13pm UTC](https://discuss.elastic.co/t/hyphenation-decompounder-token-filter-seems-to-ignore-the-only-longest-match-option/294047/4 "2022-02-09T17:13:00Z")
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