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CHECK_JSON

Checks the validity of a JSON document. If the input string is a valid JSON document or a NULL, the output is NULL. If the input cannot be translated to a valid JSON value, the output string contains the error message.

Syntax​

CHECK_JSON(<expr>)

Arguments​

ArgumentsDescription
<expr>An expression of string type

Return Type​

String

Examples​

SELECT check_json('[1,2,3]');
+-----------------------+
| check_json('[1,2,3]') |
+-----------------------+
| NULL                  |
+-----------------------+

SELECT check_json('{"key":"val"}');
+-----------------------------+
| check_json('{"key":"val"}') |
+-----------------------------+
| NULL                        |
+-----------------------------+

SELECT check_json('{"key":');
+----------------------------------------------+
| check_json('{"key":')                        |
+----------------------------------------------+
| EOF while parsing a value at line 1 column 7 |
+----------------------------------------------+