json基础应用
CREATE TABLE test_json(id INT PRIMARY KEY ,u_name VARCHAR(20),info json);
insert插入json记录
插入json数组
INSERT INTO test_json VALUES(1,'tom',json_array(99,'测试',NULL,TRUE,CURTIME()));
mysql> SELECT * FROM test_json;
+----+--------+-----------------------------------------------+
| id | u_name | info |
+----+--------+-----------------------------------------------+
| 1 | tom | [99, "测试", null, true, "23:03:35.000000"] |
+----+--------+-----------------------------------------------+
1 row in set (0.00 sec)
插入json对象（自动转换成k-v形式）
INSERT INTO test_json VALUES(2,'jerry',json_object('age',15,'time',NOW()));
mysql> SELECT * FROM test_json;
+----+--------+---------------------------------------------------+
| id | u_name | info |
+----+--------+---------------------------------------------------+
| 1 | tom | [99, "测试", null, true, "23:03:35.000000"] |
| 2 | jerry | {"age": 15, "time": "2020-06-19 23:07:24.000000"} |
+----+--------+---------------------------------------------------+
2 rows in set (0.00 sec)
INSERT INTO test_json VALUES(3,'jerry','{"city":"北京市","`time`":"2020-06-19 23:07:28"}');
mysql> SELECT * FROM test_json;
+----+--------+--------------------------------------------------------+
| id | u_name | info |
+----+--------+--------------------------------------------------------+
| 1 | tom | [99, "测试", null, true, "23:03:35.000000"] |
| 2 | jerry | {"age": 15, "time": "2020-06-19 23:07:24.000000"} |
| 3 | jerry | {"city": "北京市", "`time`": "2020-06-19 23:07:28"} |
+----+--------+--------------------------------------------------------+
select查询json记录
mysql> SELECT json_extract(info,'$.age') FROM test_json;
+----------------------------+
| json_extract(info,'$.age') |
+----------------------------+
| NULL |
| 15 |
| NULL |
+----------------------------+
3 rows in set (0.00 sec)
mysql> SELECT json_extract(info,'$.age','$.city') FROM test_json;
+-------------------------------------+
| json_extract(info,'$.age','$.city') |
+-------------------------------------+
| NULL |
| [15] |
| ["北京市"] |
+-------------------------------------+
3 rows in set (0.00 sec)
查询key
mysql> select id,json_keys(info) from test_json;
+----+--------------------+
| id | json_keys(info) |
+----+--------------------+
| 1 | NULL |
| 2 | ["age", "time"] |
| 3 | ["city", "`time`"] |
+----+--------------------+
3 rows in set (0.00 sec)
update 修改记录
增加键
UPDATE test_json SET info = json_set(info,'$.ip','10.0.0.10') WHERE id =3;
mysql> SELECT * FROM test_json;
+----+--------+---------------------------------------------------------------------------+
| id | u_name | info |
+----+--------+---------------------------------------------------------------------------+
| 1 | tom | [99, "测试", null, true, "23:03:35.000000"] |
| 2 | jerry | {"age": 15, "time": "2020-06-19 23:07:24.000000"} |
| 3 | jerry | {"ip": "10.0.0.10", "city": "北京市", "`time`": "2020-06-19 23:07:28"} |
+----+--------+---------------------------------------------------------------------------+
3 rows in set (0.00 sec)
删除键
mysql> UPDATE test_json SET info = json_remove(info,'$.ip') WHERE id = 3;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> SELECT * FROM test_json;
+----+--------+--------------------------------------------------------+
| id | u_name | info |
+----+--------+--------------------------------------------------------+
| 1 | tom | [99, "测试", null, true, "23:03:35.000000"] |
| 2 | jerry | {"age": 15, "time": "2020-06-19 23:07:24.000000"} |
| 3 | jerry | {"city": "北京市", "`time`": "2020-06-19 23:07:28"} |
+----+--------+--------------------------------------------------------+
3 rows in set (0.00 sec)