mysql中,通过json_insert函数向json字段插入键值?json_insert函数的使用?

需求描述:

　　通过json_insert向json字段中插入值,在此进行实验,记录下.

操作过程:

1.查看已经有的包含json数据类型的表

mysql> select * from tab_json;
+----+------------------------------------------------------------------------------------------------+
| id | data                                                                                           |
+----+------------------------------------------------------------------------------------------------+
|  1 | {"age": "33", "tel": 13249872314, "name": "Mike", "address": "Shenzhen", "passcode": "654567"} |
|  2 | {"age": "33", "tel": 189776542, "name": "David", "olds": "12", "address": "Hangzhou"}          |
+----+------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

2.通过json_insert来插入值

mysql> update tab_json set data = json_insert(data,"$.age","22") where id = 1;  #对一个已经存在的key进行操作,值没有变化
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1  Changed: 0  Warnings: 0

mysql> select * from tab_json;
+----+------------------------------------------------------------------------------------------------+
| id | data                                                                                           |
+----+------------------------------------------------------------------------------------------------+
|  1 | {"age": "33", "tel": 13249872314, "name": "Mike", "address": "Shenzhen", "passcode": "654567"} |
|  2 | {"age": "33", "tel": 189776542, "name": "David", "olds": "12", "address": "Hangzhou"}          |
+----+------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

mysql> update tab_json set data = json_insert(data,"$.CARD","1989833333") where id = 1;  #对不存在的key进行操作,结果是增加了key-value值
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from tab_json;
+----+----------------------------------------------------------------------------------------------------------------------+
| id | data                                                                                                                 |
+----+----------------------------------------------------------------------------------------------------------------------+
|  1 | {"age": "33", "tel": 13249872314, "CARD": "1989833333", "name": "Mike", "address": "Shenzhen", "passcode": "654567"} |
|  2 | {"age": "33", "tel": 189776542, "name": "David", "olds": "12", "address": "Hangzhou"}                                |
+----+----------------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

备注:所以json_insert函数的作用就是插入,插入不存在的键值对,如果对于一个已经存在的key进行操作是没有变化的

 

文档创建时间:2018年6月5日22:06:43