how to make a query on a field I have not defined a mapping for - elasticsearch

Question

I have a field current_country that I am adding to brands, and which has not been defined in my elasticsearch mapping.
I would like to do a filtered query on this, since it is not defined I suppose it is not analyzed and a term query should work.
This is the query I am doing
{
"index": "products",
"type": "brand",
"body": {
"from": 0,
"size": 100,
"sort": [
{
"n_name": "asc"
}
],
"query": {
"filtered": {
"query": {
"function_score": {
"filter": {
"bool": {
"must": [
{
"term": {
"current_country": "DK"
}
}
]
}
}
}
}
}
}
}
}
which returns no documents from the index.
I run the following query to check if current country exists
{
"index": "products",
"type": "brand",
"body": {
"from": 0,
"size": 100,
"sort": [
{
"n_name": "asc"
}
],
"query": {
"filtered": {
"query": {
"function_score": {
"filter": {
"bool": {
"must": [
{
"exists": {
"field": "current_country"
}
}
]
}
}
}
}
}
}
}
}
which returns a total of 693 documents.
here is an example document from the index, returned when I ran the query above.
{
"_index": "products",
"_type": "brand",
"_id": "195da951241478LuxoLivingbrand",
"_score": null,
"_source": {
"categories": [
"Bordlamper og designer bordlamper der giver liv og lys"
],
"image": "http://www.fotoagent.dk/single_picture/11385/138/mega/and_tradition_flowerpot_bordlampe_lilla.jpg",
"top_price": 1695,
"low_price": 1695,
"n_name": "&Tradition",
"name": "&Tradition",
"current_country": "DK",
"current_currency": "DKK"
}
}
How can I query against current_country (preferably a filtered query).

Answer 1

If you do not define any mapping for a field, elasticsearch tries to detect the field as string/date/numeric. If it detects the field as string then it will use the default analyzer (standard analyzer) to analyze your input. Since standard analyzer uses lowercase token filter your input string is indexed as "dk". As term filters does not analyze the input, "DK" won't match "dk".
It can be solved by various means.
(hack) You can lowercase your input filter term. this won't work for phrases.
(better) define a mapping for your input. You can dynamically change mapping/ add new mapping easily