How to update JSON data type column in MySQL 5.7.10?

Question

I have started using MySQL 5.7.10 recently and I am liking the native JSON Data type a lot.

But I ran into a problem when it comes to updating a JSON type value.

Answer 1

Now with MySQL 5.7.22+ it is very easy and straightforward to update the whole fragment of json (multiple key values, or even nested) in a single query like this:

update t1 set data = 
JSON_MERGE_PATCH(`data`, '{"key2": "I am ID2", "key3": "I am ID3"}') where id = 2;

Hope it helps someone visiting this page and looking for a "better" JSON_SET :) More about JSON_MERGE_PATCH here: https://dev.mysql.com/doc/refman/5.7/en/json-modification-functions.html#function_json-merge-patch

Answer 2

Thanks @wchiquito for pointing me right direction. I solved the problem. Here is how I did it.

mysql> select * from t1;
+----------------------------------------+------+
| data                                   | id   |
+----------------------------------------+------+
| {"key1": "value1", "key2": "VALUE2"}   |    1 |
| {"key2": "VALUE2"}                     |    2 |
| {"key2": "VALUE2"}                     |    1 |
| {"a": "x", "b": "y", "key2": "VALUE2"} |    1 |
+----------------------------------------+------+
4 rows in set (0.00 sec)

mysql> update t1 set data = JSON_SET(data, "$.key2", "I am ID2") where id = 2;
Query OK, 1 row affected (0.04 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from t1;
+----------------------------------------+------+
| data                                   | id   |
+----------------------------------------+------+
| {"key1": "value1", "key2": "VALUE2"}   |    1 |
| {"key2": "I am ID2"}                   |    2 |
| {"key2": "VALUE2"}                     |    1 |
| {"a": "x", "b": "y", "key2": "VALUE2"} |    1 |
+----------------------------------------+------+
4 rows in set (0.00 sec)

mysql> update t1 set data = JSON_SET(data, "$.key3", "I am ID3") where id = 2;
Query OK, 1 row affected (0.07 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from t1;
+------------------------------------------+------+
| data                                     | id   |
+------------------------------------------+------+
| {"key1": "value1", "key2": "VALUE2"}     |    1 |
| {"key2": "I am ID2", "key3": "I am ID3"} |    2 |
| {"key2": "VALUE2"}                       |    1 |
| {"a": "x", "b": "y", "key2": "VALUE2"}   |    1 |
+------------------------------------------+------+
4 rows in set (0.00 sec)

---

EDIT: If you want to add an array, use JSON_ARRAY like

update t1 set data = JSON_SET(data, "$.key4", JSON_ARRAY('Hello','World!')) where id = 2;