Query with entity set returns empty result

[jheeffer]

The following query should return the same datapoint data as with "key": ["geo","time"] but instead returns an empty result.

Also see correct DDFcsv reader behaviour (fixed recently): https://jsfiddle.net/jasperh/gxcdd8v4/11/

Query:

{
  "language": "en",
  "from": "datapoints",
  "animatable": "time",
  "select": {
    "key": [
      "country",
      "time"
    ],
    "value": [
      "income_per_person_gdppercapita_ppp_inflation_adjusted"
    ]
  },
  "where": {
    "$and": [
      {
        "time": "$time"
      }
    ]
  },
  "join": {
    "$time": {
      "key": "time",
      "where": {
        "time": {
          "$gte": "1993",
          "$lte": "2015"
        }
      }
    }
  },
  "order_by": [
    "time"
  ],
  "dataset": "open-numbers/ddf--gapminder--systema_globalis"
}