var config1 = {
  "type": "bar",
  "url": "https://services.arcgis.com/uDTUpUPbk8X8mXwl/arcgis/rest/services/Public_Schools_in_Onondaga_County/FeatureServer/0",
  "query": {
    "orderByFields": "Number_of_SUM DESC",
    "groupByFieldsForStatistics": "Type",
    "outStatistics": [
      {
        "statisticType": "sum",
        "onStatisticField": "Number_of",
        "outStatisticFieldName": "Number_of_SUM"
      }
    ]
  },
  "mappings": {
    "category": {"field": Type, "label": Type},
    "series": [
      {
        "field": "Number_of_SUM",
        "label": "Number of Students"
      }
    ]
  },
  "overrides": {
    "categoryAxis": {
      "labelRotation": -45
    }
  }
}

showChart("chartdiv1", config1);