ElasticSearch - Search for complete phrase only - elasticsearch

Question

I am trying to create a search that will return me exactly what i requested.
For instance let's say i have 2 documents with a field named 'Val'
First doc have a value of 'a - Copy', second document is 'a - Copy (2)'
My goal is to search exactly the value 'a - Copy' and find only the first document in my returned results and not both of them with different similarity rankings
When i try most of the usual queries like:
GET test/_search
{
"query": {
"match": {
"Val": {
"query": "a - copy",
"type": "phrase"
}
}
}
}
or:
GET /test/doc/_search
{
"query": {
"query_string": {
"default_field": "Val",
"query": "a - copy"
}
}
}
I get both documents all the time

Answer 1

There is a very good documentation for finding exact values in ES:
https://www.elastic.co/guide/en/elasticsearch/guide/current/_finding_exact_values.html
It shows you how to use the term filter and it mentions problems with analyzed fields, too.
To put it in a nutshell you need to run a term filter like this (I've put your values in):
GET /test/doc/_search
{
"query" : {
"filtered" : {
"query" : {
"match_all" : {}
},
"filter" : {
"term" : {
"Val" : "a - copy"
}
}
}
}
}
However, this doesn't work with analyzed fields. You won't get any results.
To prevent this from happening, we need to tell Elasticsearch that
this field contains an exact value by setting it to be not_analyzed.
There are multiple ways to achieve that. e.g. custom field mappings.

Answer 2

Yes, you are getting that because your field is, most likely, analyzed and split into tokens.
You need an analyzer similar to this one
"custom_keyword_analyzer": {
"type": "custom",
"tokenizer": "keyword",
"filter": "lowercase"
}
which uses the keyword tokenizer and the lowercase filter (I noticed you indexed upper case letters, but expect to search with lowercase letters).
And then use a term filter to search your documents.