Elasticsearch term query issue - elasticsearch

Question

As the pictures show the record field of dispatchvoucher value is "True".
But when I searched with the term it couldn´t found any record.
when I changed the value to "true", the result matched. What's the reason for this?

Answer 1

As mentioned in the documentation :
Avoid using the term query for text fields.
By default, Elasticsearch changes the values of text fields as part of
analysis. This can make finding exact matches for text field values
difficult.
To search text field values, use the match query instead.
The standard analyzer is the default analyzer which is used if none is specified. It provides grammar-based tokenization.
GET /_analyze
{
"analyzer" : "standard",
"text" : "True"
}
The token generated is -
{
"tokens": [
{
"token": "true",
"start_offset": 0,
"end_offset": 4,
"type": "<ALPHANUM>",
"position": 0
}
]
}
Term query returns documents that contain an exact term in a provided field. Since True gets tokenized to true, so when you are using the term query for "dispatchvoucher": "True", it will not show any results.
You can either change your index mapping to
{
"mappings": {
"properties": {
"dispatchvoucher": {
"type": "keyword"
}
}
}
}
OR You need to add .keyword to the dispatchvoucher field. This uses the keyword analyzer instead of the standard analyzer (notice the ".keyword" after dispatchvoucher field).
Adding a working example with index data, search query, and search result
Index Data:
{
"dispatchvoucher": "True"
}
Search Query:
{
"query": {
"bool": {
"filter": {
"term": {
"dispatchvoucher.keyword": "True"
}
}
}
}
}
Search Result:
"hits": [
{
"_index": "65605120",
"_type": "_doc",
"_id": "1",
"_score": 0.0,
"_source": {
"dispatchvoucher": "True"
}
}
]