Categories:
Semi-structured Data Functions (Type Predicates)

IS_<object_type>

This family of functions serves as Boolean predicates that can be used to determine the data type of a value stored in a VARIANT column:

See also:
AS_<object_type> , TYPEOF

General Usage Notes

  • All the functions are unary, taking a VARIANT expression as the only argument.
  • All the functions return FALSE if the input is SQL NULL or the VARIANT expression contains null.

Examples

These examples use the vartab table (created in the PARSE_JSON examples):

select n, v, typeof(v) from vartab;

+---+------------------------+------------+
| 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              |            |
|   | }                      |            |
+---+------------------------+------------+

Count all rows in vartab table where the VARIANT column v contains a string value:

select count(*) from vartab where is_char(v);

+----------+
| COUNT(*) |
|----------|
|        1 |
+----------+

Select rows in vartab table where the VARIANT column v contains the specified data type:

select * from vartab where is_null_value(v);

+---+------+
| N | V    |
|---+------|
| 1 | null |
+---+------+

select * from vartab where is_boolean(v);

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

select * from vartab where is_integer(v);

+---+-----+
| N | V   |
|---+-----|
| 4 | -17 |
+---+-----+

select * from vartab where is_decimal(v);

+---+--------+
| N | V      |
|---+--------|
| 4 | -17    |
| 5 | 123.12 |
+---+--------+

select * from vartab where is_double(v);

+---+-----------------------+
| N | V                     |
|---+-----------------------|
| 4 | -17                   |
| 5 | 123.12                |
| 6 | 1.912000000000000e+02 |
+---+-----------------------+

select * from vartab where is_varchar(v);

+---+------------------------+
| N | V                      |
|---+------------------------|
| 7 | "Om ara pa ca na dhih" |
+---+------------------------+

select * from vartab where is_array(v);

+---+-------------+
| N | V           |
|---+-------------|
| 8 | [           |
|   |   -1,       |
|   |   12,       |
|   |   289,      |
|   |   2188,     |
|   |   false,    |
|   |   undefined |
|   | ]           |
+---+-------------+

select * from vartab where is_object(v);

+---+---------------+
| N | V             |
|---+---------------|
| 9 | {             |
|   |   "x": "abc", |
|   |   "y": false, |
|   |   "z": 10     |
|   | }             |
+---+---------------+