how to exclude search words in synonyms filter in elasticsearch - elasticsearch

Question

While I'm adding table and tables as synonym filter in elastic search, I need to filter out the results for table fan. How to achieve this in elastic search
Could we build a taxonomy of inclusion and exclusion lists filters in settings rather than at run time queries in elastic search

Answer 1

GET <indexName>/_search
{
"query": {
"bool": {
"must_not": [
{
"match": {
"<fieldName>": {
"query": "table fan", // <======= Below operator will applied b/w table(&synonyms) And fan(&synonyms)
"operator": "AND"
}
}
}
]
}
}
}
You can use above query to exclude all the documents having both 'table', 'fan' and their corresponding synonyms.
OR:
If you want to play with multiple logical operators. e.g Given me all the documents which doesn't contain either "table fan" Or "ac" you can use simple_query_string
GET <indexName>/_search
{
"query": {
"bool": {
"must_not": [
{
"simple_query_string": {
"query": "(table + fan) | ac", // <=== '+'='and', '|'='or', '-'='not'
"fields": [
"<fieldName>" // <==== use multiple field names, wildcard also supported
]
}
}
]
}
}
}

Answer 2

Adding a working example with index data, mapping, search query and search result
Index Mapping:
{
"settings": {
"index": {
"analysis": {
"filter": {
"synonym_filter": {
"type": "synonym",
"synonyms": [
"table, tables"
]
}
},
"analyzer": {
"synonym_analyzer": {
"tokenizer": "standard",
"filter": [
"lowercase",
"synonym_filter"
]
}
}
}
}
},
"mappings": {
"properties": {
"title": {
"type": "text",
"analyzer": "synonym_analyzer",
"search_analyzer": "standard"
}
}
}
}
Analyze API
POST/_analyze
{
"analyzer" : "synonym_analyzer",
"text" : "table fan"
}
The following tokens are generated:
{
"tokens": [
{
"token": "table",
"start_offset": 0,
"end_offset": 5,
"type": "<ALPHANUM>",
"position": 0
},
{
"token": "tables",
"start_offset": 0,
"end_offset": 5,
"type": "SYNONYM",
"position": 0
},
{
"token": "fan",
"start_offset": 6,
"end_offset": 9,
"type": "<ALPHANUM>",
"position": 1
}
]
}
Index Data:
{ "title": "table and fan" }
{ "title": "tables and fan" }
{ "title": "table fan" }
{ "title": "tables fan" }
{ "title": "table chair" }
Search Query:
{
"query": {
"bool": {
"must": {
"match": {
"title": "table"
}
},
"filter": {
"bool": {
"must_not": [
{
"match_phrase": {
"title": "table fan"
}
},
{
"match_phrase": {
"title": "table and fan"
}
}
]
}
}
}
}
}
You can also use match query in place of match_phrase query
{
"query": {
"bool": {
"must": {
"match": {
"title": "table"
}
},
"filter": {
"bool": {
"must_not": [
{
"match": {
"title": {
"query": "table fan",
"operator": "AND"
}
}
}
]
}
}
}
}
}
Search Result:
"hits": [
{
"_index": "synonym",
"_type": "_doc",
"_id": "2",
"_score": 0.06783115,
"_source": {
"title": "table chair"
}
}
]
Update 1:
Could we build a taxonomy of inclusion and exclusion lists filters in
settings rather than at run time queries in elastic search
Mapping is the process of defining how a document, and the fields it contains, are stored and indexed.Refer this ES documentation on mapping to understand what mapping is used to define.
Please refer to this documentation on Dynamic template that allow you to define custom mappings that can be applied to dynamically added fields