# Understanding search-as-you-type Fields **URL:** \ **Category:** Elasticsearch\ **Created:** [November 7, 2023, 9:43pm UTC](https://discuss.elastic.co/t/understanding-search-as-you-type-fields/346661 "2023-11-07T21:43:54Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![safakkbilici](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/safakkbilici/32/136311_2.png) [@safakkbilici](https://discuss.elastic.co/u/safakkbilici)\ **Post date:** [November 7, 2023, 9:43pm UTC](https://discuss.elastic.co/t/understanding-search-as-you-type-fields/346661/1 "2023-11-07T21:43:54Z")
Hello community, I am using ES on my local machine with version of 8.10.4 I was experimenting with search-as-you-type lately and I am confused by ".\_2gram" and ".\_3gram" fields. I created a basic index as ```json PUT autosuggest_trial_2 { "mappings": { "properties": { "description": { "type": "search_as_you_type", "analyzer": "my_custom_analyzer" } } }, "settings": { "analysis": { "filter": { "my_ascii_folding": { "type": "asciifolding" } }, "analyzer": { "my_custom_analyzer": { "type": "custom", "tokenizer": "standard", "filter": ["lowercase", "my_ascii_folding", "trim"] } } } } } ``` Then I built a search query as: ```json GET autosuggest_trial_2/_search { "query": { "bool": { "must": { "multi_match": { "query": "for men shoe", "fields": [ "description", "description._2gram", "description._3gram" ], "type": "bool_prefix", "operator": "AND" } } } } } ``` The results are exactly what I wanted to see. However, when I remove `"description._2gram"` and `"description._3gram"` from fields in search query, the results are same. So, I am confused about why I give these fields. Also, some examples added `"._index_prefix"` as well. When I add `"profile": true` to my search query, I can see that search query uses `"description._2gram"` and that's a relief. Maybe elasticsearch adds these fields automatically? Is there an explanation as to why? Thanks. ---
**Author:** ![carly.richmond](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/carly.richmond/32/104935_2.png) [@carly.richmond](https://discuss.elastic.co/u/carly.richmond)\ **Post date:** [November 8, 2023, 10:55am UTC](https://discuss.elastic.co/t/understanding-search-as-you-type-fields/346661/2 "2023-11-08T10:55:29Z")
Hi @safakkbilici, Welcome to the community! The `._2gram` and `._3gram` fields are generated by default as the default `max_shingle_size` is 3 [as per the documentation](https://www.elastic.co/guide/en/elasticsearch/reference/current/search-as-you-type.html). When you used the `"profile" : true` option with all fields included the query are you seeing that it's using both the 2 and 3 gram fields? ---
**Author:** ![ashishtiwari1993](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/ashishtiwari1993/32/135241_2.png) [@ashishtiwari1993](https://discuss.elastic.co/u/ashishtiwari1993)\ **Post date:** [November 9, 2023, 4:36pm UTC](https://discuss.elastic.co/t/understanding-search-as-you-type-fields/346661/3 "2023-11-09T16:36:43Z")
Hello @safakkbilici, Indeed you will get same result. But this can match the query terms in any order, but it will score documents higher if they contain the terms in order in a shingle subfield. For example I am indexing below doc ## Create index ```auto PUT products { "mappings": { "properties": { "description": { "type": "search_as_you_type" } } } } ``` ## Index Docs ```auto POST products/_doc/ { "description": "best jogging shoes for men" } ``` ```auto POST products/_doc/ { "description": "I purchased best sport shoes for upcoming match" } ``` ## Query 1 ```auto GET products/_search { "query": { "multi_match": { "query": "best sport jogging", "type": "bool_prefix", "fields": [ "description" ] } } } ``` ### Response ```auto { "took": 9, "timed_out": false, "_shards": { "total": 1, "successful": 1, "skipped": 0, "failed": 0 }, "hits": { "total": { "value": 2, "relation": "eq" }, "max_score": 1.201328, "hits": [ { "_index": "products", "_id": "i5HdtIsBDw1I7eA1_uoH", "_score": 1.201328, "_source": { "description": "best jogging shoes for men" } }, { "_index": "products", "_id": "jJHktIsBDw1I7eA1supk", "_score": 0.79994905, "_source": { "description": "I purchased best sport shoes for upcoming match" } } ] } } ``` If you have noticed, We still getting record but best match is coming on second rank. Because in this query only term `jogging` is getting matched but my expectation was doc which contains `best sport` should come first. Lets try another query ## Query 2 ```auto GET products/_search { "query": { "multi_match": { "query": "best sport jogging", "type": "bool_prefix", "fields": [ "description", "description._2gram", "description._3gram" ] } } } ``` ### Response ```auto { "took": 12, "timed_out": false, "_shards": { "total": 1, "successful": 1, "skipped": 0, "failed": 0 }, "hits": { "total": { "value": 2, "relation": "eq" }, "max_score": 1.4235239, "hits": [ { "_index": "products", "_id": "jJHktIsBDw1I7eA1supk", "_score": 1.4235239, "_source": { "description": "I purchased best sport shoes for upcoming match" } }, { "_index": "products", "_id": "i5HdtIsBDw1I7eA1_uoH", "_score": 1.201328, "_source": { "description": "best jogging shoes for men" } } ] } } ``` This time I am getting proper order because `best sport` term is matched with `description._2gram` field. Hence it boost the score. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [December 7, 2023, 4:37pm UTC](https://discuss.elastic.co/t/understanding-search-as-you-type-fields/346661/4 "2023-12-07T16:37:16Z")
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