<geopoint_column>.<lat/lon> cannot pass semantic analyzer

[chloe-zh]

Data sample: kibana_sample_data_flights

Example query:

POST _opendistro/_sql
{
  "query": "select DestLocation.lon from kibana_sample_data_flights limit 3"
}

Output:

{
  "error": {
    "reason": "Invalid SQL query",
    "details": "Field [DestLocation.lon] cannot be found or used here.",
    "type": "SemanticAnalysisException"
  },
  "status": 400
}

Expected result:

{
  "took" : 0,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 10000,
      "relation" : "gte"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "kibana_sample_data_flights",
        "_type" : "_doc",
        "_id" : "JmzfNG8Bks2M7WBSzhwy",
        "_score" : 1.0,
        "_source" : {
          "DestLocation" : {
            "lon" : "151.177002"
          }
        }
      },
      {
        "_index" : "kibana_sample_data_flights",
        "_type" : "_doc",
        "_id" : "J2zfNG8Bks2M7WBSzhwy",
        "_score" : 1.0,
        "_source" : {
          "DestLocation" : {
            "lon" : "12.3519"
          }
        }
      },
      {
        "_index" : "kibana_sample_data_flights",
        "_type" : "_doc",
        "_id" : "KGzfNG8Bks2M7WBSzhwy",
        "_score" : 1.0,
        "_source" : {
          "DestLocation" : {
            "lon" : "12.3519"
          }
        }
      }
    ]
  }
}

[chloe-zh]

Related issue: #313