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As_<Type>

Strict casting VARIANT values to other data types. If the input data type is not VARIANT, the output is NULL. If the type of value in the VARIANT does not match the output value, the output is NULL.

Syntax​

AS_BOOLEAN( <variant> )
AS_INTEGER( <variant> )
AS_FLOAT( <variant> )
AS_STRING( <variant> )
AS_ARRAY( <variant> )
AS_OBJECT( <variant> )

Arguments​

ArgumentsDescription
<variant>The VARIANT value

Return Type​

  • AS_BOOLEAN: Boolean
  • AS_INTEGER: Int64
  • AS_FLOAT: Float64
  • AS_STRING: String
  • AS_ARRAY: Variant contains Array
  • AS_OBJECT: Variant contains Object

Examples​

SELECT as_boolean(parse_json('true'));
+--------------------------------+
| as_boolean(parse_json('true')) |
+--------------------------------+
| 1                              |
+--------------------------------+

SELECT as_integer(parse_json('123'));
+-------------------------------+
| as_integer(parse_json('123')) |
+-------------------------------+
| 123                           |
+-------------------------------+

SELECT as_float(parse_json('12.34'));
+-------------------------------+
| as_float(parse_json('12.34')) |
+-------------------------------+
| 12.34                         |
+-------------------------------+

SELECT as_string(parse_json('"abc"'));
+--------------------------------+
| as_string(parse_json('"abc"')) |
+--------------------------------+
| abc                            |
+--------------------------------+

SELECT as_array(parse_json('[1,2,3]'));
+---------------------------------+
| as_array(parse_json('[1,2,3]')) |
+---------------------------------+
| [1,2,3]                         |
+---------------------------------+

SELECT as_object(parse_json('{"k":"v","a":"b"}'));
+--------------------------------------------+
| as_object(parse_json('{"k":"v","a":"b"}')) |
+--------------------------------------------+
| {"k":"v","a":"b"}                          |
+--------------------------------------------+