Trends visualisation with filter

[osakout]

Hi,

I tried to create trend visualization with question, it works well, but when i want to filter it in dashboard filter, it display me that there is no comparison vs previous data.

I tried the same visualization with native request (mongodb), and im facing with a new problem, Metabase tell me that i need to aggregate by a time field, it's already done.
I tried limit my request, i tried date field to be the first field, i tried convert date, obviously to date format, i tried to exclude null values, i also used the UI to generate native query from the question that display trend visualization

here is my native query

[
      {
    "$match": {
      "created_at": { "$exists": true, "$ne": null }
    }
  },
  {
    "$group": {
      "_id": {
        "created_at": {
          "$dateTrunc": {
            "date": "$created_at",
            "unit": "month",
            "timezone": "Europe/Paris"
          }
        }
      },
      "count": {
        "$sum": 1
      }
    }
  },
  {
    "$project": {
      "_id": false,
      "count": true,
            "date": {
          "$convert": {
              "input": "$_id.created_at",
              "to": "date"
          }
      },
    }
  },
    {
    "$sort": {
      "date": -1
    },
  },
  {
      "$limit": 2
  }
]

Thanks for you help

[Luiggi]

Hi, we're working to make this happen in v49. What's the data you see in the table (collection in this case) when the query is run?

[osakout]

Hi Luiggi,

Here is data i see when query is run
I added a limit of 2 to have only current value VS previous value, i also tried without limit