# Indexing and searching on special characters? **URL:** \ **Category:** Elasticsearch\ **Created:** [October 11, 2012, 7:36am UTC](https://discuss.elastic.co/t/indexing-and-searching-on-special-characters/9312 "2012-10-11T07:36:46Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![tsandstr](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tsandstr](https://discuss.elastic.co/u/tsandstr)\ **Post date:** [October 11, 2012, 7:36am UTC](https://discuss.elastic.co/t/indexing-and-searching-on-special-characters/9312/1 "2012-10-11T07:36:46Z")
I am having some troubles with how the indexing works on strings. I use normal mapping for strings and query\_string for my queries. I index the following: curl -XPUT [http://localhost:9200/twitter/tweet/1](http://localhost:9200/twitter/tweet/1) -d '{ "message": "A&B: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/2](http://localhost:9200/twitter/tweet/2) -d '{ "message": "A+B: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/3](http://localhost:9200/twitter/tweet/3) -d '{ "message": "A-B: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/4](http://localhost:9200/twitter/tweet/4) -d '{ "message": "A_B: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/5](http://localhost:9200/twitter/tweet/5) -d '{ "message": "A&C: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/6](http://localhost:9200/twitter/tweet/6) -d '{ "message": "A+C: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/7](http://localhost:9200/twitter/tweet/7) -d '{ "message": "A-C: This is just a test" }' curl -XPUT [http://localhost:9200/twitter/tweet/8](http://localhost:9200/twitter/tweet/8) -d '{ "message": "A_C: This is just a test" }' and I get the following results with my queries: {'query': {'query\_string': {'query': 'A+B', 'default\_operator': 'AND', 'default\_field': 'message'}}} {u'message': u'A&B: This is just a test'} {u'message': u'A+B: This is just a test'} {u'message': u'A-B: This is just a test'} {u'message': u'A\*B: This is just a test'} --\> I Expected to get only: A+B: This is just a test {'query': {'query\_string': {'query': 'A&B', 'default\_operator': 'AND', 'default\_field': 'message'}}} {u'message': u'A&B: This is just a test'} {u'message': u'A+B: This is just a test'} {u'message': u'A-B: This is just a test'} {u'message': u'A\*B: This is just a test'} --\> I Expected to get only: A&B: This is just a test {'query': {'query\_string': {'query': 'A\*B', 'default\_operator': 'AND', 'default\_field': 'message'}}} --\> Got no results at all, this is VERY confusing {'query': {'query\_string': {'query': 'A-B', 'default\_operator': 'AND', 'default\_field': 'message'}}} {u'message': u'A&B: This is just a test'} {u'message': u'A+B: This is just a test'} {u'message': u'A-B: This is just a test'} {u'message': u'A\*B: This is just a test'} --\> I Expected to get only: A&B: This is just a test {'query': {'query\_string': {'query': 'A B', 'default\_operator': 'AND', 'default\_field': 'message'}}} {u'message': u'A&B: This is just a test'} {u'message': u'A+B: This is just a test'} {u'message': u'A-B: This is just a test'} {u'message': u'A\*B: This is just a test'} Why does the query A\*B not return anything at all? Is there a simple way to know how special characters are indexed by default? It seems to me that A&B, A+B and A-B are all indexed the same way as A B, am I correct? What about all other characters? How do they behave and how should I construct my query in order to get correct results? Escaping them does not seem to help. Any help would be appreciated. Thank you! - Tommy ---
**Author:** ![tsandstr](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tsandstr](https://discuss.elastic.co/u/tsandstr)\ **Post date:** [October 11, 2012, 11:31am UTC](https://discuss.elastic.co/t/indexing-and-searching-on-special-characters/9312/2 "2012-10-11T11:31:43Z")
Nevermind, it seems that I should escape all extra characters. And since the standard analyzer either replaces the special character with spaces or does something else. I will end up with several results no mather which special character is used. This is okay for me, since I do not really care about the extra characters and do not need a search on them. In some cases though it could be good to do the indexing of the extra characters too. But I guess the only way to do that is to create an own analyzer and use it? One more question. How are endings such as 's handled? For example: Twitter's I would rather remove the 's endings, instead of having them, during index. Can this behaviour be easily achieved? - Tommy ---
**Author:** ![Chris\_Male](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/chris_male/32/2607_2.png) [@Chris\_Male](https://discuss.elastic.co/u/Chris_Male)\ **Post date:** [October 13, 2012, 7:14am UTC](https://discuss.elastic.co/t/indexing-and-searching-on-special-characters/9312/3 "2012-10-13T07:14:01Z")
Tommy, On Friday, October 12, 2012 12:31:43 AM UTC+13, tommy wrote: > Nevermind, it seems that I should escape all extra characters. And since > the > standard analyzer either replaces the special character with spaces or > does > something else. I will end up with several results no mather which special > character is used. > > This is okay for me, since I do not really care about the extra characters > and do not need a search on them. > > In some cases though it could be good to do the indexing of the extra > characters too. But I guess the only way to do that is to create an own > analyzer and use it? StandardAnalyzer is really just built of a Tokenizer and a number of TokenFilters. To have different behaviour (such as indexing extra characters) you can just define a new Analyzer your ES mapping which uses a different Tokenizer or TokenFilters. > One more question. How are endings such as 's handled? For example: > Twitter's > > I would rather remove the 's endings, instead of having them, during > index. > Can this behaviour be easily achieved? > > - Tommy > > -- > View this message in context: > [http://elasticsearch-users.115913.n3.nabble.com/Indexing-and-searching-on-special-characters-tp4023761p4023781.html](http://elasticsearch-users.115913.n3.nabble.com/Indexing-and-searching-on-special-characters-tp4023761p4023781.html) > Sent from the Elasticsearch Users mailing list archive at [Nabble.com](http://Nabble.com). -- ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 3:08am UTC](https://discuss.elastic.co/t/indexing-and-searching-on-special-characters/9312/4 "2017-07-06T03:08:57Z")