elasticsearch/docs/reference/query-languages/esql/_snippets/functions/to_double.md

TO_DOUBLE [esql-to_double]

Syntax

:::{image} ../../../../../images/to_double.svg :alt: Embedded :class: text-center :::

Parameters

field : Input value. The input can be a single- or multi-valued column or an expression.

Description

Converts an input value to a double value. If the input parameter is of a date type, its value will be interpreted as milliseconds since the Unix epoch, converted to double. Boolean true will be converted to double 1.0, false to 0.0.

Supported types

field	result
boolean	double
counter_double	double
counter_integer	double
counter_long	double
date	double
double	double
integer	double
keyword	double
long	double
text	double
unsigned_long	double

Example

ROW str1 = "5.20128E11", str2 = "foo"
| EVAL dbl = TO_DOUBLE("520128000000"), dbl1 = TO_DOUBLE(str1), dbl2 = TO_DOUBLE(str2)

str1:keyword	str2:keyword	dbl:double	dbl1:double	dbl2:double
5.20128E11	foo	5.20128E11	5.20128E11	null

Note that in this example, the last conversion of the string isn’t possible. When this happens, the result is a null value. In this case a Warning header is added to the response. The header will provide information on the source of the failure:

"Line 1:115: evaluation of [TO_DOUBLE(str2)] failed, treating result as null. Only first 20 failures recorded."

A following header will contain the failure reason and the offending value: "java.lang.NumberFormatException: For input string: "foo""