Elasticsearch returning unexpected results - elasticsearch

Question

I used following mapping:
I have modified english analyzer to use ngram analyzer as follows,so that I should be able to search under following scenarios :
1] partial search and special character search
2] To get advantage of language analyzers
{
"settings": {
"analysis": {
"analyzer": {
"english_ngram": {
"type": "custom",
"filter": [
"english_possessive_stemmer",
"lowercase",
"english_stop",
"english_stemmer",
"ngram_filter"
],
"tokenizer": "whitespace"
}
},
"filter": {
"english_stop": {
"type": "stop"
},
"english_stemmer": {
"type": "stemmer",
"language": "english"
},
"english_possessive_stemmer": {
"type": "stemmer",
"language": "possessive_english"
},
"ngram_filter": {
"type": "edge_ngram",
"min_gram": 1,
"max_gram": 25
}
}
}
},
"mappings": {
"movie": {
"properties": {
"title": {
"type": "string",
"fields": {
"en": {
"type": "string",
"analyzer": "english_ngram"
}
}
}
}
}
}
}
Indexed my data as follows:
PUT http://localhost:9200/movies/movie/1
{
"title" : "$peci#l movie"
}
Query as follows:
{
"query": {
"multi_match": {
"query": "$peci#44 m11ov",
"fields": ["title.en"],
"operator":"and",
"type": "most_fields",
"minimum_should_match": "75%"
}
}
}
In query I am looking for "$peci#44 m11ov" string ,ideally I should not get results for this.
Anything wrong in here ?

Answer 1

This is a result of ngram tokenization. When you tokenize a string $peci#l movie your analyzer produces tokens like $, $p, $pe, etc. Your query also produces most of these tokens. Though these matches will have a lower score than a complete match. If it's critical for you to exclude these false positive matches, you can try to set a threshold using min_score option https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-min-score.html