SELECT
name, profile->"$.twitter" AS `twitter`
FROM `user`
WHERE
profile->"$.twitter" IS NOT NULL;
https://dev.mysql.com/doc/refman/5.7/en/json-search-functions.html
https://www.sitepoint.com/use-json-data-fields-mysql-databases/
w 动态条数入表为一个字段 计算的便利性
https://dev.mysql.com/doc/refman/5.7/en/json.html
As of MySQL 5.7.8, MySQL supports a native JSON data type that enables efficient access to data in JSON (JavaScript Object Notation) documents. The JSON data type provides these advantages over storing JSON-format strings in a string column:
Comparison and Ordering of JSON Values
JSON values can be compared using the =, <, <=, >, >=, <>, !=, and <=> operators.
The following comparison operators and functions are not yet supported with JSON values:
http://www.w.com/new/amzapi/amzapitest_com/MarketplaceWebServiceOrders/Samples/ListOrdersSample.php


w
w同时存string(sql string)、json转化后的string(sql string)、json(sql json)进行对比。

https://dev.mysql.com/doc/refman/5.7/en/json.html
ALTER TABLE w ADD pic_json JSON;
