JSON_DEPTH

Description

Returns the maximum depth of a JSON document.

Syntax

JSON_DEPTH(json_doc)

Remarks

The json_doc parameter specifies the JSON document. If the parameter is NULL, NULL is returned.

An error is returned if the parameter is not a valid JSON document.

The depth of an empty array, empty object, or scalar value is 1. The depth of a non-empty array that contains only elements with a depth of 1 is 2. The depth of a non-empty object that contains only members with a value of depth 1 is 2. Otherwise, the depth of the JSON document is greater than 2.

Examples

SELECT JSON_DEPTH('{}'), JSON_DEPTH('[]'), JSON_DEPTH('true');
+------------------+------------------+--------------------+
| JSON_DEPTH('{}') | JSON_DEPTH('[]') | JSON_DEPTH('true') |
+------------------+------------------+--------------------+
|                1 |                1 |                  1 |
+------------------+------------------+--------------------+
1 row in set (0.001 sec)

SELECT JSON_DEPTH('[101, 202]'), JSON_DEPTH('[[], {}]');
+--------------------------+------------------------+
| JSON_DEPTH('[101, 202]') | JSON_DEPTH('[[], {}]') |
+--------------------------+------------------------+
|                        2 |                      2 |
+--------------------------+------------------------+
1 row in set (0.001 sec)

SELECT JSON_DEPTH('[101, {"a": 202}]');
+---------------------------------+
| JSON_DEPTH('[101, {"a": 202}]') |
+---------------------------------+
|                               3 |
+---------------------------------+
1 row in set (0.001 sec)

SELECT JSON_DEPTH('{"a":101, "v":"aaa"}');
+------------------------------------+
| JSON_DEPTH('{"a":101, "v":"aaa"}') |
+------------------------------------+
|                                  2 |
+------------------------------------+
1 row in set (0.001 sec)