# Regexp Query cannot escape reserved symbols **URL:** \ **Category:** Elasticsearch\ **Created:** [November 21, 2017, 7:46am UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527 "2017-11-21T07:46:39Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Hayk\_Hovhanisyan](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hayk_hovhanisyan/32/77342_2.png) [@Hayk\_Hovhanisyan](https://discuss.elastic.co/u/Hayk_Hovhanisyan)\ **Post date:** [November 21, 2017, 7:46am UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/1 "2017-11-21T07:46:39Z")
**My environment:** _ElasticSearch "2.4.4"_ _Java "1.8.0\_151"_ Hi there, please clarify for me part of escaping reserved symbols . ? + \* | { } [] ( ) " I used [backslash](https://www.elastic.co/guide/en/elasticsearch/reference/2.4/query-dsl-regexp-query.html#allowed-characters), but result still empty. I stored displayName= AB\*CD, and I am trying search b\*c peace of code which responsible to adding filter: queryBuilder.filter(boolQuery().must(regexpQuery(columnName, ".\*" + regexValue.toLowerCase() + ".\*"))); ``` { "from":0, "size":10, "query":{ "bool":{ "must":{ "match_all":{ } }, "filter":[ { "bool":{ "must":{ "regexp":{ "displayName":{ "value":".*b\\*c.*", "flags_value":65535 } } } } }, { "terms":{ "deleted":[ "false" ] } } ] } }, "_source":{ "includes":[ "id", "displayName" ], "excludes":[ ] }, "sort":[ { "displayName":{ "order":"asc" } } ] } ``` 1. What's wrong here? 2. Do we need use **whitespace analyzer** instead of **standart analyzer**? 3. Do we need change **tokinizer** as well? ---
**Author:** ![jpountz](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jpountz/32/45836_2.png) [@jpountz](https://discuss.elastic.co/u/jpountz)\ **Post date:** [November 21, 2017, 1:37pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/2 "2017-11-21T13:37:42Z")
The standard analyzer splits on `*` so a regular expression that expects to find a `*` would never match any documents. Indeed, a whitespace tokenizer might work. I'd also like to point out that regexp queries are super slow, especially if there are wildcards in the beginning like here, so I would advise to do things differently if possible. For instance, this particular use-case could be solved by indexing 3-grams. ---
**Author:** ![Hayk\_Hovhanisyan](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hayk_hovhanisyan/32/77342_2.png) [@Hayk\_Hovhanisyan](https://discuss.elastic.co/u/Hayk_Hovhanisyan)\ **Post date:** [November 22, 2017, 2:28pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/3 "2017-11-22T14:28:17Z")
Thanks for your quick answer Adrien. As I understand if we use default analyzer which is standard analyzer, there is no way for searching with reserved symbols at all `. ? + * | { } [] ( ) " \`. Solution 1: Use indexing 3-grams - it means add some n-gram(in our case 3 grams) tokenizer and so on. Solution 2: Use some Pattern tokenizer with our new analyzer? One more question: Does this part of documentation not about if we use standard analyzer? _ **Allowed characters** _ **Any Unicode characters may be used in the pattern, but certain characters are reserved and must be escaped. The standard reserved characters are:** `. ? + * | { } [] ( ) " \` If you enable optional features (see below) then these characters may also be reserved: `# @ & < > ~` Any reserved character can be escaped with a backslash "\*" including a literal backslash character: "\" **Additionally, any characters (except double quotes) are interpreted literally when surrounded by double quotes:** `john"@smith.com"` Thanks a lot for your time. ---
**Author:** ![jpountz](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jpountz/32/45836_2.png) [@jpountz](https://discuss.elastic.co/u/jpountz)\ **Post date:** [November 22, 2017, 3:33pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/4 "2017-11-22T15:33:32Z")
> [@Hayk\_Hovhanisyan](#): > > As I understand if we use default analyzer which is standard analyzer, there is no way for searching with reserved symbols at all This is correct. > [@Hayk\_Hovhanisyan](#): > > Does this part of documentation not about if we use standard analyzer? This is a generic advice. Obviously it is irrelevant with analyzers that split on those chars. For instance if you field is mapped as a `keyword`, it applies. ---
**Author:** ![Hayk\_Hovhanisyan](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hayk_hovhanisyan/32/77342_2.png) [@Hayk\_Hovhanisyan](https://discuss.elastic.co/u/Hayk_Hovhanisyan)\ **Post date:** [November 22, 2017, 4:17pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/5 "2017-11-22T16:17:36Z")
Thanks a lot Adrien, will think about solution. If will be any update from my side I will put here. Thanks again for your time and support ---
**Author:** ![Hayk\_Hovhanisyan](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hayk_hovhanisyan/32/77342_2.png) [@Hayk\_Hovhanisyan](https://discuss.elastic.co/u/Hayk_Hovhanisyan)\ **Post date:** [December 20, 2017, 7:00am UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/6 "2017-12-20T07:00:05Z")
Hi Adrien one more question about searching. When we use standard analyzer and have index analyzed, with symbol [space] there is no way for searching as well? For instance, firstname [space] surname(ex: Hayk Hovhannisyan), is not returning any results. if the user enter for example "Ha Hov" then it should find "Hayk Hovhannisyan" as well. And need relations AND. At this moment I used REGEXP query , and have analyzed field for that. What can you suggest me for that? thanks in advance regards Hayk Hovhannisyan ---
**Author:** ![Hayk\_Hovhanisyan](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hayk_hovhanisyan/32/77342_2.png) [@Hayk\_Hovhanisyan](https://discuss.elastic.co/u/Hayk_Hovhanisyan)\ **Post date:** [December 21, 2017, 12:41pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/7 "2017-12-21T12:41:31Z")
What you think about this ? One idea is instead of regexp match using Fuzzy Query Match and play with fuzziness and operator properties. regards Hayk Hovhannisyan ---
**Author:** ![jpountz](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jpountz/32/45836_2.png) [@jpountz](https://discuss.elastic.co/u/jpountz)\ **Post date:** [December 21, 2017, 2:05pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/8 "2017-12-21T14:05:50Z")
The usual way that this would be done would be to use an edge-ngram filter in the index analyzer (but not in the search analyzer) and then use regular match queries for searching. ---
**Author:** ![Hayk\_Hovhanisyan](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/hayk_hovhanisyan/32/77342_2.png) [@Hayk\_Hovhanisyan](https://discuss.elastic.co/u/Hayk_Hovhanisyan)\ **Post date:** [December 22, 2017, 8:56am UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/9 "2017-12-22T08:56:27Z")
Hi Adrien thanks for quick response. Did you mean ? [Index Time Search As You Type](https://www.elastic.co/guide/en/elasticsearch/guide/current/_index_time_search_as_you_type.html) ---
**Author:** ![jpountz](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jpountz/32/45836_2.png) [@jpountz](https://discuss.elastic.co/u/jpountz)\ **Post date:** [December 22, 2017, 9:50am UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/10 "2017-12-22T09:50:15Z")
Yes, this is a good example. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [January 19, 2018, 1:27pm UTC](https://discuss.elastic.co/t/regexp-query-cannot-escape-reserved-symbols/108527/12 "2018-01-19T13:27:11Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.