# Allow the reverse token filter to be used in normalizers? **URL:** \ **Category:** Elasticsearch\ **Created:** [September 27, 2017, 10:17pm UTC](https://discuss.elastic.co/t/allow-the-reverse-token-filter-to-be-used-in-normalizers/102038 "2017-09-27T22:17:44Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![apang](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/apang/32/22400_2.png) [@apang](https://discuss.elastic.co/u/apang)\ **Post date:** [September 27, 2017, 10:17pm UTC](https://discuss.elastic.co/t/allow-the-reverse-token-filter-to-be-used-in-normalizers/102038/1 "2017-09-27T22:17:44Z")
I was trying to index a "keyword" datatype field by its reversal in a multi-field mapping but it seems that the _reverse_ token filter is not allowed in a normalizer. I wanted to enable a "suffix query" (ends with) without the search performance penalty of using a wildcard query with a starting '\*'. With the reversed "keyword" indexed, it is then possible to use the prefix query for an efficient suffix query. Currently I'm working around the restriction on the normalizer by using a custom analyzer on the "text" datatype using the keyword tokenizer, but if it is possible to use a normalizer that would be preferred. The docs say > Only the filters that work on a per-character basis are allowed Can someone confirm if the reverse token filter meets that requirement or not? I would think that a reverse operation could work on a per-character basis. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [October 25, 2017, 10:18pm UTC](https://discuss.elastic.co/t/allow-the-reverse-token-filter-to-be-used-in-normalizers/102038/2 "2017-10-25T22:18:28Z")
Closed on October 25, 2017, 10:18pm UTC This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.