JSON_MERGE_PRESERVE(json_doc, json_doc[, json_doc] ...)Merges the given JSON documents, returning the merged result, or NULL if any argument is NULL.
JSON_MERGE_PRESERVE is a synonym for JSON_MERGE, which has been deprecated.
Unlike JSON_MERGE_PATCH, members with duplicate keys are preserved.
SET @json1 = '[1, 2]';
SET @json2 = '[2, 3]';
SELECT JSON_MERGE_PATCH(@json1,@json2),JSON_MERGE_PRESERVE(@json1,@json2);
+---------------------------------+------------------------------------+
| JSON_MERGE_PATCH(@json1,@json2) | JSON_MERGE_PRESERVE(@json1,@json2) |
+---------------------------------+------------------------------------+
| [2, 3] | [1, 2, 2, 3] |
+---------------------------------+------------------------------------+This page is licensed: CC BY-SA / Gnu FDL