Elasticsearch wildcard case-sensitive - elasticsearch

Question

How to make wildcard case-insensitive?
https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-wildcard-query.html

Answer 1

Since version 7.10 the wildcard query supports special parameter case_insensitive (boolean).
Example of case-insensitive search:
GET /_search
{
"query": {
"wildcard": {
"my_field": {
"value": "ki*y",
"case_insensitive": true
}
}
}
}

Answer 2

Wildcards are not_analyzed. It depends on what analyzers you've provided for the field you're searching. But if you're using the default analyzers then a wildcard query will return case-insensitive results.
Example: Post two names in a sample index one is "Sid" and other "sid".
POST sample/sample
{
"name" : "sid"
}
POST sample/sample
{
"name" : "Sid"
}
Then perform a wildcard query:
GET sample/_search
{
"query": {
"wildcard": {
"name": {
"value": "s*"
}
}
}
}
This will return me both the documents:
{
"took": 10,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 2,
"max_score": 1,
"hits": [
{
"_index": "sample",
"_type": "sample",
"_id": "AWRPM87Wb6oopELrnEKE",
"_score": 1,
"_source": {
"name": "Sid"
}
},
{
"_index": "sample",
"_type": "sample",
"_id": "AWRPM9tpb6oopELrnEKF",
"_score": 1,
"_source": {
"name": "sid"
}
}
]
}
}
But if you perform a wildcard query on "S*" it will return nothing. Because the default token filter stores the terms in lowercase and the term "Sid" is stored as "sid" in the inverted index.

Answer 3

In my case this is not true, it is case sensitive by default - I am using ES 7.2.
In you sample the type of the field is "text" not "keyword"

Answer 4

I was looking for the same option for nodejs client, so came across this question, so posting as an answer might help someone else.
I have to convert the term to lowercase and its worked for me *${term.toLowerCase()}*
Here is the complete function
searchUsers(term, from, limit) {
let users = await EsClient.search({
index: 'users',
type: 'users',
body: {
from,
size: limit,
query: {
bool: {
should: [
{
wildcard: {
email: {
value: `*${term.toLowerCase()}*`
}
}
},
{
wildcard: {
"name.keyword": {
value: `*${term.toLowerCase()}*`
}
}
}
],
must_not: {
terms: {_id: blacklist}
}
}
}
}
});
}