Sorting on an array of strings in ElasticSearch

Question

I'm using the following to sort documents in Elasticsearch that have a 'usernamesAssigned' property. usernamesAssigned is an array of strings:

"sort": [
    {
        "_script": {
            "script": "doc["usernamesAssigned"].values.sort().join()",
            "type": "string",
            "lang": "js",
            "order": "asc"
        }
    }
]

I'm wondering if there's a more efficient way to do this without using script based sorting?

Answer 1

This is an old question, but I recently wandered across it while trying to solve the same problem...

According to the documentation:

Elasticsearch supports sorting by array or multi-valued fields. The mode option controls what array value is picked for sorting the document it belongs to.

So, you should be able to sort like this:

"sort" : [ {"usernamesAssigned" : {"order" : "asc", "mode" : "min"}} ]

This has been available since version 0.90.0.Beta1.