Define cube key

[leonorsilva]

When I try to redefine the cube's key it appears as it does not change.
This is my model:

    "cubes": [
    	{
            "name": "un_hi",
            "dimensions": [
                "date",
                "location",
                "transport"
            ],
            "key": 
            	"ag_id"
            ,
            "joins":[
                 {"master":"un_hi.eid",
                 "detail":"agency_event.eid"}
            ],
            "aggregates": [
                {
                    "name": "record_count",
                    "function": "count"
                }
            ],
            "mappings": {
                "location.latitude": "un_hi.latitude",
                "location.longitude": "un_hi.longitude",
                "transport.unityp":"un_hi.unityp"
            }
      }
]

So I am trying to change the key to ag_id, but then the browser is doing this query:

What am I doing wrong?
Thank you for your time!