Find documents with empty string value on elasticsearch

Question

I\'ve been trying to filter with elasticsearch only those documents that contains an empty string in its body. So far I\'m having no luck.

Before I go on, I should

Answer 1

For those of you using elastic search 5.2 or above, and still stuck. Easiest way is to reindex your data correctly with the keyword type. Then all the searches for empty values worked. Like this:

"query": {
    "term": {"MY_FIELD_TO_SEARCH": ""}
}

Actually, when I reindex my database and rerun the query. It worked =)

The problem was that my field was type: text and NOT a keyword. Changed the index to keyword and reindexed:

curl -X PUT https://username:password@host.io:9200/mycoolindex

curl -X PUT https://user:pass@host.io:9200/mycoolindex/_mapping/mycooltype -d '{
  "properties": {
            "MY_FIELD_TO_SEARCH": {
                    "type": "keyword"
                },
}'

curl -X PUT https://username:password@host.io:9200/_reindex -d '{
 "source": {
   "index": "oldindex"
 },
 "dest": {
    "index": "mycoolindex"
 }
}'

I hope this helps someone who was as stuck as I was finding those empty values.