mysql5.7之json格式与json_extract方法使用

数据初始化

json_test表数据，id和jsonstr字段(类型json)

{
    "no": "7",
    "title": "运动方式",
    "content": [{
        "text": "您平时经常进行的运动及时间",
        "item1": [{
            "text": "慢跑 / 快走 / 走跑结合",
            "type": "select",
            "value": "selected"
        }, {
            "text": "上下楼梯 / 爬山",
            "type": "multselect",
            "value": "selected"
        }],
        "item2": [{
            "text": "慢跑222走跑结合",
            "type": "text",
            "value": "慢跑2"
        }, {
            "text": "上下楼梯 / 爬山2",
            "type": "number",
            "value": "33"
        }]
    }]
}

select语句

SELECT
    id,
    json_extract( t.jsonstr, '$.*' ),
    json_extract( t.jsonstr, '$.title' ) AS "title",
    json_extract( t.jsonstr, '$.content' ) AS "content" ,
    json_extract( t.jsonstr, '$**.text' ) AS "text" ,
    json_extract( t.jsonstr, '$.content[*].item1[*]' ) AS "item1" 
FROM
    json_test t;

返回结果解析

//json_extract( t.jsonstr, '$.*' )返回：
["7", "运动方式", [{"text": "您平时经常进行的运动及时间", "item1": [{"text": "慢跑 / 快走 / 走跑结合", "type": "select", "value": "selected"}, {"text": "上下楼梯 / 爬山", "type": "multselect", "value": "selected"}], "item2": [{"text": "慢跑222走跑结合", "type": "text", "value": "慢跑2"}, {"text": "上下楼梯 / 爬山2", "type": "number", "value": "33"}]}]]

//json_extract( t.jsonstr, '$.title' ) AS "title"返回：
"运动方式"

//json_extract( t.jsonstr, '$.content' ) AS "content" 返回：
[{"text": "您平时经常进行的运动及时间", "item1": [{"text": "慢跑 / 快走 / 走跑结合", "type": "select", "value": "selected"}, {"text": "上下楼梯 / 爬山", "type": "multselect", "value": "selected"}], "item2": [{"text": "慢跑222走跑结合", "type": "text", "value": "慢跑2"}, {"text": "上下楼梯 / 爬山2", "type": "number", "value": "33"}]}]

//json_extract( t.jsonstr, '$**.text' ) AS "text" 返回：
["您平时经常进行的运动及时间", "慢跑 / 快走 / 走跑结合", "上下楼梯 / 爬山", "慢跑222走跑结合", "上下楼梯 / 爬山2"]

//json_extract( t.jsonstr, '$.content[*].item1[*]' ) AS "item1" 返回：
[{"text": "慢跑 / 快走 / 走跑结合", "type": "select", "value": "selected"}, {"text": "上下楼梯 / 爬山", "type": "multselect", "value": "selected"}]

用法解析

‘$.*’	返回全部json
‘$.title’	返回key=”title”的数据
‘$**.text’	返回所有最底层key=”text”的数据
‘$.content[*].item1[*]’	返回key=content的list的key=item1的list的所有内容

官方文档

https://dev.mysql.com/doc/refman/5.7/en/json.html