I need to get the last document field to visualize

[dotnet85]

I have created an index and I would like to get the latest value available in the index

e.g.:

{
  "_index": "tester",
  "_type": "_doc",
  "_id": "Qujl-nMBaIdydddddd",
  "_version": 1,
  "_score": 0,
  "_source": {
    "brd_part_no": "55-a54tt-08",
    "brd_rev": "B",
    "operator_id": "0230057",
    "serial_no": "sdeiek649",
    "test_status": "06",
    "start_time": "200303224308",
    "test_time": "000079",
    "end_time": "200303224427",
    "sent_time": "2020-08-17T13:30:08.670463"
  },
  "fields": {
    "end_time": [
      "2020-03-03T22:44:27.000Z"
    ],
    "sent_time": [
      "2020-08-17T13:30:08.670Z"
    ],
    "start_time": [
      "2020-03-03T22:43:08.000Z"
    ]
  }
}

I would like to get the latest serial no available and visualize it:

Current Serial Number: < Latest Serial Number >

Is there a way to retrieve the latest-record serial number

thank you

[matw (Matthias Wilhelm)]

Hi

Would something like this work? It's the metric visualization of Kibana, you would just need to switch the field to serial_no, and sort by sent_time (I think that's the date when it was sent to Elasticsearch)?

Best,
Matthias

[dotnet85]

thank you Matthias for the swift reply
I have tried this earlier, but didn't help as I didn't see serial_no field in the list of fields.

Is there something wrong in the mapping

even manully writing the field name indicates there is no field match

{
  "mapping": {
    "properties": {
      "brd_part_no": {
        "type": "text"
      },
      "brd_rev": {
        "type": "text"
      },
      "end_time": {
        "type": "date",
        "format": "yyMMddHHmmss"
      },
      "operator_id": {
        "type": "text"
      },
      "sent_time": {
        "type": "date"
      },
      "serial_no": {
        "type": "text",
        "fielddata": true
      },
      "start_time": {
        "type": "date",
        "format": "yyMMddHHmmss"
      },
      "test_status": {
        "type": "text"
      },
      "test_time": {
        "type": "integer"
      },
      "tester_host": {
        "type": "text"
      }
    }
  }
}

yes I think sent_time is the time when the record was sent to ES

Thank you

[matw (Matthias Wilhelm)]

You should switch the type of serial_no to "keyword" ... here's why:

Keyword type family | Elasticsearch Reference [7.9] | Elastic

Best,
Matthias

[dotnet85]

thank you Matthias,

after changing the field type to keyword, it worked.

Thanks!