match query no has result for custom analyzer - elasticsearch

Question

I have two index:
First:
curl -XPUT 'http://localhost:9200/first/' -d '
{
"mappings": {
"product": {
"properties": {
"name": {
"type": "string",
"analyzer":"spanish"
}
}
}
}
}
'
Second:
curl -XPUT 'http://localhost:9200/second/' -d '
{
"mappings": {
"product": {
"properties": {
"name": {
"type": "string",
"analyzer":"spanish_custom"
}
}
}
},
"settings": {
"analysis": {
"filter": {
"spanish_stop": {
"type": "stop",
"stopwordsPath": "spanish_stop_custom.txt"
},
"spanish_stemmer": {
"type": "stemmer",
"language": "spanish"
}
},
"analyzer": {
"spanish_custom": {
"tokenizer": "standard",
"filter": [
"standard",
"lowercase",
"spanish_stop",
"spanish_stemmer"
]
}
}
}
}
}
'
I insert some document for both index:
curl -XPOST 'http://localhost:9200/first/product' -d '
{
"name": "Hidratante"
}'
curl -XPOST 'http://localhost:9200/second/product' -d '
{
"name": "Hidratante"
}'
i checked tokens for the field name:
curl -XGET 'http://localhost:9200/first/_analyze?field=name' -d 'hidratante'
{"tokens":[{"token":"hidratant","start_offset":0,"end_offset":10,"type":"<ALPHANUM>","position":1}]}
curl -XGET 'http://localhost:9200/second/_analyze?field=name' -d 'hidratante'
{"tokens":[{"token":"hidrat","start_offset":0,"end_offset":10,"type":"<ALPHANUM>","position":1}]}
I want search for 'hidratant' and give results in both index, but i got results only first index
My Query:
curl -XGET 'http://127.0.0.1:9200/first/_search' -d '
{
"query" : {
"multi_match" : {
"query" : "hidratant",
"fields" : [ "name"],
"type" : "phrase_prefix",
"operator" : "AND",
"prefix_length" : 3,
"tie_breaker": 1
}
}
}
'
First index result:
{"took":6,"timed_out":false,"_shards":{"total":5,"successful":5,"failed":0},"hits":{"total":2,"max_score":0.5945348,"hits":[{"_index":"test","_type":"product","_id":"AVPxjvpRDl8qAEgsMFMu","_score":0.5945348,"_source":
{
"name": "Hidratante"
}},{"_index":"test","_type":"product","_id":"AVPxkYbKDl8qAEgsMFMv","_score":0.5945348,"_source":
{
"name": "Hidratante"
}}]}}
Second index result:
{"took":1,"timed_out":false,"_shards":{"total":5,"successful":5,"failed":0},"hits":{"total":0,"max_score":null,"hits":[]}}
Why the second index no has return result?

Answer 1

As you mentioned in your question above, for second index the tokens being generated for the term Hidratanteare:
{"tokens":[{"token":"hidrat","start_offset":0,"end_offset":10,"type":"<ALPHANUM>","position":1}]}
There is a concept of search analyzer which comes in when you perform search operation. According to the documentation:
By default, queries will use the analyzer defined in the field mapping while searching.
So when you run phrase_prefix query , same custom analyzer created by you will act on name field in second index.
Since you are searching for keyword : hidratant
It gets analyzed as :
For first Index:
curl -XGET 'http://localhost:9200/first/_analyze?field=name' -d 'hidratant'
{
"tokens": [
{
"token": "hidratant",
"start_offset": 3,
"end_offset": 12,
"type": "<ALPHANUM>",
"position": 1
}
]
}
i.e why you get result in first index.
For second index:
curl -XGET 'http://localhost:9200/second/_analyze?field=name' -d 'hidratant'
{
"tokens": [
{
"token": "hidratant",
"start_offset": 3,
"end_offset": 12,
"type": "<ALPHANUM>",
"position": 1
}
]
}
The token generated while searching is hidratant but it was hidrat while indexing. That's why you don't get any result in second case.