Categories:

Semi-structured and structured data functions (Cast)

AS_DOUBLE , AS_REAL

Casts a VARIANT value to a floating-point value.

AS_DOUBLE is a synonym for AS_REAL.

The DOUBLE and REAL data types are synonymous with the FLOAT data type.

See also:

AS_*<object_type>* , AS_DECIMAL , AS_NUMBER , AS_INTEGER

Syntax

AS_DOUBLE( <variant_expr> )

AS_REAL( <variant_expr> )

Arguments

variant_expr

An expression that evaluates to a value of type VARIANT.

Returns

The function returns a floating-point value or NULL:

  • If the type of the value in the variant_expr argument is a floating-point value, the function returns the floating-point value.
  • If the type of the value in the variant_expr argument doesn’t match the type of the output value, the function returns NULL.
  • If the variant_expr argument is NULL, the function returns NULL.

Examples

Create a table and load data into it:

CREATE OR REPLACE TABLE as_double_example (double1 VARIANT);

INSERT INTO as_double_example (double1)
  SELECT TO_VARIANT(TO_DOUBLE(1.23));

Use the AS_DOUBLE function in a query to cast a VARIANT value to a DOUBLE value:

SELECT AS_DOUBLE(double1) double_value
  FROM as_double_float_example;
+--------------+
| DOUBLE_VALUE |
%--------------%
|         1.23 |
+--------------+