Mango search in Arrays

Question

My document has a structure like this:

{
  \"Calibration\": {
    \"Presettings\": {
      \"Date\": [
        {
          \"Value\": \"2016-09-02 10:11\",
          


        

Answer 1

First, you need to create your index. I suggest that you create an index on the Calibration.Presettings.Date field.

You can use the following JSON object to create it:

{
  "index": {
    "fields": [
      "_id",
      "Calibration.Presettings.Date.[].Type"
    ]
  },
  "type": "json"
}

So the selector would be like this :

{
  "selector": {
    "Calibration.Presettings.Date": {
      "$elemMatch": {
        "$and": [
          {
            "Type": "generated"
          },
          {
            "Value": {
              "$gte": "2016-09-01"
            }
          }
        ]
      }
    }
  }
}

We execute the query on the field Calibration.Pressettings.Date which is an Array. Since it's an array, we have to use the $elemMatch operator.

Then, we have a $and condition for the Value and the Type.

The Type of the Date has to be generated. With can either use the $eq operator or simply use this simple syntax: {"field":"value"}.

Finally, the Date`s Value must be greater or equal to X date. We can use the $gte operator.