Is there a way to "escape" ElasticSearch stop words? - elasticsearch

Question

I am fairly new to ElasticSearch and have a question on stop words. I have an index that contains state names for the USA....ex: New York/NY, California/CA,Oregon/OR. I believe Oregon's abbreviation, 'OR' is a stop word, so when I insert the state data into the index, I cannot search on 'OR'. Is there a way I can set up custom stopwords for this or am I doing something wrong?
Here is how I am building the index:
curl -XPUT http://localhost:9200/test/state/1 -d '{"stateName": ["California","CA"]}'
curl -XPUT http://localhost:9200/test/state/2 -d '{"stateName": ["New York","NY"]}'
curl -XPUT http://localhost:9200/test/state/3 -d '{"stateName": ["Oregon","OR"]}'
A search for 'NY', works fine. Ex:
curl -XGET 'http://localhost:9200/test/state/_search?pretty=1' -d '
{
"query" : {
"match" : {
"stateName" : "NY"
}
}
}'
But a search for 'OR', returns zero hits:
curl -XGET 'http://localhost:9200/test/state/_search?pretty=1' -d '
{
"query" : {
"match" : {
"stateName" : "OR"
}
}
}'
I believe this search returns no results because OR is stop word, but I don't know how to work around this. Thanks for you help.

Answer 1

You can (and definitely should) control the way you index data by modifying your mapping according to your data and the way you want to search against it.
In your case I would disable stopwords for that specific field rather than modifying the stopword list, but you could do the latter too if you wish to. The point is that you're using the default mapping which is great to start with, but as you can see you need to tweak it depending on your needs.
For each field, you can specify what analyzer to use. An analyzer defines the way you split your text into tokens (tokenizer) that will be indexed and also additional changes you can make to each token (even remove or add new ones) using token filters.
You can specify your mapping either while creating your index or update it afterwards using the put mapping api (as long as the changes you make are backwards compatible).