Ruby/Mutate: converting to double

[chuchurocket27]

Based on the documentation for the mutate filter it looks like I cannot convert a value to a double, only a float.

Is there a way with a Ruby filter to convert to a double instead?

[magnusbaeck (Magnus Bäck)]

"float" should be interpreted as "floating-point number", not "the single-precision floating-point data type known from C". All floating-point numbers in Ruby (and therefore Logstash) have double precision.

[chuchurocket27]

Interesting, thanks for the info. That's inconsistent with Elasticsearch's numeric types where they do differentiate between float and double.

Problem I'm having is, I'm using Dremio to sit between ES and some business intelligence software that only speaks SQL. Dremio enforces what it finds from the mapping - i.e., since the mapping is float, it will cast the value to float even though ES has a double in the field.

Here is the mapping of a sample ES document:

{
  "double_test": {
    "mappings": {
      "test_point": {
        "properties": {
          "value": {
            "type": "float"
          }
        }
      }
    }
  }
}

and the document itself:

{
  "_index": "double_test",
  "_type": "test_point",
  "_id": "1",
  "_version": 1,
  "found": true,
  "_source": {
    "value": 3.141592653589793
  }
}

Within Dremio, the value is strictly interpreted as a float:

So I suppose my next question now is, is there a way to set up ES such that the default numeric type is double, not float? (I realize that I can set mappings, but the name of the field is not constant.)

[magnusbaeck (Magnus Bäck)]

This is really an Elasticsearch question, but you should be able to do something with dynamic mappings.