Categories:: Semi-structured and structured data functions (Type Predicates)

IS_BOOLEAN¶

Returns TRUE if its VARIANT argument contains a BOOLEAN value.

See also:: IS_<object_type>

Syntax¶

IS_BOOLEAN( <variant_expr> )

Arguments¶

variant_expr: An expression that evaluates to a value of type VARIANT.

Returns¶

Returns a BOOLEAN value or NULL.

Returns TRUE if the VARIANT value contains a BOOLEAN value. Otherwise, returns FALSE.
If the input is NULL, returns NULL without reporting an error.

Examples¶

The following examples use the IS_BOOLEAN function.

Use the IS_BOOLEAN function in a WHERE clause¶

Create and fill the vartab table. The INSERT statement uses the PARSE_JSON function to insert VARIANT values in the v column of the table.

CREATE OR REPLACE TABLE vartab (n NUMBER(2), v VARIANT);

INSERT INTO vartab
  SELECT column1 AS n, PARSE_JSON(column2) AS v
    FROM VALUES (1, 'null'), 
                (2, null), 
                (3, 'true'),
                (4, '-17'), 
                (5, '123.12'), 
                (6, '1.912e2'),
                (7, '"Om ara pa ca na dhih"  '), 
                (8, '[-1, 12, 289, 2188, false,]'), 
                (9, '{ "x" : "abc", "y" : false, "z": 10} ') 
       AS vals;

Query the data. The query uses the TYPEOF function to show the data types of the values stored in the VARIANT column.

SELECT n, v, TYPEOF(v)
  FROM vartab
  ORDER BY n;

+---+------------------------+------------+
| N | V                      | TYPEOF(V)  |
|---+------------------------+------------|
| 1 | null                   | NULL_VALUE |
| 2 | NULL                   | NULL       |
| 3 | true                   | BOOLEAN    |
| 4 | -17                    | INTEGER    |
| 5 | 123.12                 | DECIMAL    |
| 6 | 1.912000000000000e+02  | DOUBLE     |
| 7 | "Om ara pa ca na dhih" | VARCHAR    |
| 8 | [                      | ARRAY      |
|   |   -1,                  |            |
|   |   12,                  |            |
|   |   289,                 |            |
|   |   2188,                |            |
|   |   false,               |            |
|   |   undefined            |            |
|   | ]                      |            |
| 9 | {                      | OBJECT     |
|   |   "x": "abc",          |            |
|   |   "y": false,          |            |
|   |   "z": 10              |            |
|   | }                      |            |
+---+------------------------+------------+

Show the BOOLEAN values in the data by using the IS_BOOLEAN function in a WHERE clause:

SELECT * FROM vartab WHERE IS_BOOLEAN(v);

+---+------+
| N | V    |
|---+------|
| 3 | true |
+---+------+

Use the IS_BOOLEAN function in a SELECT list¶

Create and fill the multiple_types table. The INSERT statement uses the TO_VARIANT function to insert VARIANT values in the columns.

CREATE OR REPLACE TABLE multiple_types (
  array1 VARIANT,
  array2 VARIANT,
  boolean1 VARIANT,
  varchar1 VARIANT,
  varchar2 VARIANT,
  decimal1 VARIANT,
  double1 VARIANT,
  integer1 VARIANT,
  object1 VARIANT);

INSERT INTO multiple_types
    (array1, array2, boolean1, varchar1, varchar2,
     decimal1, double1, integer1, object1)
  SELECT
    TO_VARIANT(TO_ARRAY('Example')),
    TO_VARIANT(ARRAY_CONSTRUCT('Array-like', 'example')),
    TO_VARIANT(TRUE),
    TO_VARIANT('X'),
    TO_VARIANT('I am a real character'),
    TO_VARIANT(1.23::DECIMAL(6, 3)),
    TO_VARIANT(3.21::DOUBLE),
    TO_VARIANT(15),
    TO_VARIANT(TO_OBJECT(PARSE_JSON('{"Tree": "Pine"}')));

Query the data using the TYPEOF function to show the data types of the values stored in the VARIANT values.

SELECT TYPEOF(array1),
       TYPEOF(array2),
       TYPEOF(boolean1),
       TYPEOF(varchar1),
       TYPEOF(varchar2),
       TYPEOF(decimal1),
       TYPEOF(double1),
       TYPEOF(integer1),
       TYPEOF(object1)
  FROM multiple_types;

+----------------+----------------+------------------+------------------+------------------+------------------+-----------------+------------------+-----------------+
| TYPEOF(ARRAY1) | TYPEOF(ARRAY2) | TYPEOF(BOOLEAN1) | TYPEOF(VARCHAR1) | TYPEOF(VARCHAR2) | TYPEOF(DECIMAL1) | TYPEOF(DOUBLE1) | TYPEOF(INTEGER1) | TYPEOF(OBJECT1) |
|----------------+----------------+------------------+------------------+------------------+------------------+-----------------+------------------+-----------------|
| ARRAY          | ARRAY          | BOOLEAN          | VARCHAR          | VARCHAR          | DECIMAL          | DOUBLE          | INTEGER          | OBJECT          |
+----------------+----------------+------------------+------------------+------------------+------------------+-----------------+------------------+-----------------+

Show whether a column contains BOOLEAN values in the data by using the IS_BOOLEAN function in a SELECT list:

SELECT IS_BOOLEAN(boolean1),
       IS_BOOLEAN(array1)
  FROM multiple_types;

+----------------------+--------------------+
| IS_BOOLEAN(BOOLEAN1) | IS_BOOLEAN(ARRAY1) |
|----------------------+--------------------|
| True                 | False              |
+----------------------+--------------------+