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Semi-structured and 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¶

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;
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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;
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+---+------------------------+------------+
| 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_VARCHAR(v);
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+----------+
| 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);
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+---+------+
| N | V    |
|---+------|
| 1 | null |
+---+------+

SELECT * FROM vartab WHERE IS_BOOLEAN(v);
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+---+------+
| N | V    |
|---+------|
| 3 | true |
+---+------+

SELECT * FROM vartab WHERE IS_INTEGER(v);
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+---+-----+
| N | V   |
|---+-----|
| 4 | -17 |
+---+-----+

SELECT * FROM vartab WHERE IS_DECIMAL(v);
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+---+--------+
| N | V      |
|---+--------|
| 4 | -17    |
| 5 | 123.12 |
+---+--------+

SELECT * FROM vartab WHERE IS_DOUBLE(v);
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+---+-----------------------+
| N | V                     |
|---+-----------------------|
| 4 | -17                   |
| 5 | 123.12                |
| 6 | 1.912000000000000e+02 |
+---+-----------------------+

SELECT * FROM vartab WHERE IS_VARCHAR(v);
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+---+------------------------+
| N | V                      |
|---+------------------------|
| 7 | "Om ara pa ca na dhih" |
+---+------------------------+

SELECT * FROM vartab WHERE IS_ARRAY(v);
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+---+-------------+
| N | V           |
|---+-------------|
| 8 | [           |
|   |   -1,       |
|   |   12,       |
|   |   289,      |
|   |   2188,     |
|   |   false,    |
|   |   undefined |
|   | ]           |
+---+-------------+

SELECT * FROM vartab WHERE IS_OBJECT(v);
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+---+---------------+
| N | V             |
|---+---------------|
| 9 | {             |
|   |   "x": "abc", |
|   |   "y": false, |
|   |   "z": 10     |
|   | }             |
+---+---------------+
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