GraphQL join test
Re. https://github.com/grafana/grafana/issues/31104 and GraphQL
For demonstrating issue https://github.com/grafana/grafana/issues/31104 with GraphQL datasource
{
  "__inputs": [],
  "__requires": [
    {
      "type": "grafana",
      "id": "grafana",
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      {
        "builtIn": 1,
        "datasource": "-- Grafana --",
        "enable": true,
        "hide": true,
        "iconColor": "rgba(0, 211, 255, 1)",
        "name": "Annotations & Alerts",
        "type": "dashboard"
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  "editable": true,
  "gnetId": 14341,
  "graphTooltip": 0,
  "id": null,
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          "thresholds": {
            "mode": "absolute",
            "steps": [
              {
                "color": "green",
                "value": null
              },
              {
                "color": "red",
                "value": 80
              }
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        "overrides": []
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      "targets": [
        {
          "aliasBy": "",
          "annotationTags": "",
          "annotationText": "",
          "annotationTitle": "",
          "constant": 6.5,
          "dataPath": "station.timetable.nextArrivals",
          "endTimePath": "endTime",
          "groupBy": "",
          "queryText": "{\n  station:stationWithEvaId(evaId: 8000105) {\n    timetable {\n      nextArrivals {\n        platform\n        trainNumber\n      }\n    }\n  }\n}",
          "refId": "A",
          "timeFormat": null,
          "timePath": ""
        },
        {
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          "annotationTitle": "",
          "constant": 6.5,
          "dataPath": "station.timetable.nextArrivals",
          "endTimePath": "endTime",
          "groupBy": "",
          "hide": false,
          "queryText": "{\n  station:stationWithEvaId(evaId: 8000107) {\n    timetable {\n      nextArrivals {\n        platform\n        trainNumber\n      }\n    }\n  }\n}",
          "refId": "B",
          "timeFormat": null,
          "timePath": ""
        }
      ],
      "title": "Panel Title",
      "transformations": [
        {
          "id": "seriesToColumns",
          "options": {
            "byField": "platform"
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        }
      ],
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    }
  ],
  "schemaVersion": 27,
  "style": "dark",
  "tags": [],
  "templating": {
    "list": []
  },
  "time": {
    "from": "now-6h",
    "to": "now"
  },
  "timepicker": {},
  "timezone": "",
  "title": "GraphQL join test",
  "uid": "v-vkUB9Gk",
  "version": 1,
  "description": "Re. https://github.com/grafana/grafana/issues/31104 and GraphQL"
}