如何从MySQL中的JSON对象在表中存储键和值 [英] How to store a key and value in a table from a JSON object in MySQL

问题描述

我有一个MySQL数据库表，即ds_message和ds_params，它的表ds_message在每一行中都包含一个JSON对象.我想通过引用ds_message主键id

I'm having a MySQL database tables namely ds_message and ds_params, it table ds_message contains a JSON object in each row. I would like to store the key and value of a JSON object into the table ds_params for all the records by referring the ds_message primary key id

表:ds_message

Table: ds_message

_____________________________________________________________________________________
id  key_value
_____________________________________________________________________________________
1  '{"a":"John", "b":"bat", "c":"$10"}'
2  '{"i":"Emma", "j":"Jam"}'

我需要将key_value插入到另一个表中，例如

I'm required to insert the key_value into another table like

_________________________________________________
id   message_id    json_key    json_value
_________________________________________________
1    1             'a'         'John'
2    1             'b'         'bat'
3    1             'c'         '$10'
4    2             'i'         'Emma'
5    2             'j'         'Jam'

表结构:

Table Structure:

CREATE TABLE `ds_message` (
  `id` int NOT NULL,
  `key_value` varchar(500) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COMMENT='';

ALTER TABLE `ds_message`
  ADD PRIMARY KEY (`id`);

INSERT INTO `ds_message` (`id`, `key_value`) VALUES
(1, '{"a":"John", "b":"bat", "c":"$10"}');

INSERT INTO `ds_message` (`id`, `key_value`) VALUES
(2, '{"i":"Emma", "j":"Jam"}');

CREATE TABLE `ds_params` (
  `id` int NOT NULL,
  `message_id` int NOT NULL,
  `json_key` varchar(500) NOT NULL,
  `json_value` varchar(500) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COMMENT='';

ALTER TABLE `ds_params`
  ADD PRIMARY KEY (`id`);

请协助我实现此目标，它可以是简单的选择cum插入语句，也可以是通过存储过程以优化方式进行的.

Kindly assist me how to achieve this, it may be a simple select cum insert statement or by stored procedure in an optimized way.

推荐答案

使用

Use MySql JSON functions. The following information will help you writing a stored procedure which fills the table key_value from ds_message.

1. 要获取对象的键数组，请使用json_keys

 SELECT JSON_keys('{"foo": 1, "bar": 2}')

您可以使用键获取每个属性的值

You can get the value of each property using a key

 SELECT JSON_EXTRACT('{"foo": 1, "bar": 2}', '$.foo');

使用嵌套循环对ds_message记录进行迭代，并使用上述方法对每个json对象进行迭代.为每个对象中的每个键插入一条记录.

Use a nested loop to iterate the ds_message records and iterate each json object using the above methods. Insert a record for each key in each object.

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