JSON functions were added in MariaDB 10.2.3.
 
Syntax
------ 
JSON_MERGE(json_doc, json_doc[, json_doc] ...)
 
Description
----------- 
Merges the given JSON documents.
 
Returns the merged result,or NULL if any argument is NULL.
 
An error occurs if any of the arguments are not valid JSON
documents.
 
JSON_MERGE has been deprecated since MariaDB 10.2.25,
MariaDB 10.3.16 and MariaDB 10.4.5. JSON_MERGE_PATCH is an
RFC 7396-compliant replacement, and JSON_MERGE_PRESERVE is a
synonym.
 
Example
 
SET @json1 = '[1, 2]';
 
SET @json2 = '[3, 4]';
 
SELECT JSON_MERGE(@json1,@json2);
+---------------------------+
| JSON_MERGE(@json1,@json2) |
+---------------------------+
| [1, 2, 3, 4] |
+---------------------------+
 


URL: https://mariadb.com/kb/en/json_merge/