如何更新MySQL 5.7.10中的JSON数据类型列?

ʞɹᴉ*_*ʌɐp 34 mysql json mysql-5.7 mysql-json

我最近开始使用MySQL 5.7.10,我很喜欢原生的JSON数据类型.

但是在更新JSON类型值时遇到了问题.

问题:

下面是表格格式,这里我想在表格的JSON data列中再添加1个键t1.现在我必须获取值修改它并更新表.所以它涉及一个额外的SELECT声明.

我可以像这样插入

INSERT INTO t1 values ('{"key2":"value2"}', 1);

mysql> select * from t1;
+--------------------+------+
| data               | id   |
+--------------------+------+
| {"key1": "value1"} |    1 |
| {"key2": "value2"} |    2 |
| {"key2": "value2"} |    1 |
+--------------------+------+
3 rows in set (0.00 sec)

mysql>Show create table t1;


+-------+-------------------------------------------------------------

-------------------------------------------------------+
| Table | Create Table                                                                                                       |
+-------+--------------------------------------------------------------------------------------------------------------------+
| t1    | CREATE TABLE `t1` (
  `data` json DEFAULT NULL,
  `id` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
+-------+--------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
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有没有解决这个问题?

ʞɹᴉ*_*ʌɐp 67

谢谢@wchiquito指出我正确的方向.我解决了这个问题.我就是这样做的.

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)
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在此输入图像描述

  • 像这样的@siva-JSON_SET(@j,'$ .key1',10,'$ .key2','[true,false]') (3认同)

bor*_*ryn 5

现在使用 MySQL 5.7.22+,可以非常简单直接地在单个查询中更新整个 json 片段(多个键值,甚至嵌套),如下所示:

update t1 set data = 
JSON_MERGE_PATCH(`data`, '{"key2": "I am ID2", "key3": "I am ID3"}') where id = 2;
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希望它可以帮助访问此页面并寻找“更好”的人JSON_SET:) 更多关于JSON_MERGE_PATCH这里的信息:https : //dev.mysql.com/doc/refman/5.7/en/json-modification-functions.html#function_json-merge-修补

  • 另外值得一提的是,如果当前“data”为空,则此更新不起作用(据我所知,在 MySQL 8.0.13 之前,您无法为 JSON 列设置默认值)。所以你可能想做类似 `update t1 set data = JSON_MERGE_PATCH(COALESCE(\`data\`, "{}"), '{"key2": "I am ID2", "key3": "I am ID3 "}') 其中 id = 2;` (3认同)