anchor.diff:            "name": "io.debezium.data.Json",
             "version": 1,
             "field": "patch"
  +        },
  +        {
  +          "type": "string",
  +          "optional": true,
  +          "name": "io.debezium.data.Json",
  +          "version": 1,
  +          "field": "filter"
           },
           {
             "type": "struct",
  
positive.code: 
  * The `op` field value is now `u`, signifying that this document changed because of an update
  * The `patch` field appears and has the stringified JSON representation of the actual MongoDB idempotent change to the document, which in this example involves setting the `first_name` field to a new value
  * The `after` field no longer appears
  * The `source` field structure has the same fields as before, but the values are different since this event is from a different position in the oplog
  * The `ts_ms` shows the timestamp that {prodname} processed this event
  
negative.code:       "op": "u",
        "ts_ms": 1465491461815,
        "patch": "{\"$set\":{\"first_name\":\"Anne Marie\"}}",
        "filter": "{\"_id\" : {\"$numberLong\" : \"1004\"}}",
        "source": {
          "version": "{debezium-version}",
          "connector": "mongodb",
  