java 如何使用JDBC读取mysql中的JSON数据类型
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How to read JSON data type in mysql using JDBC
提问by Kushan
Mysql 5.7 introduced the JSON data type which offers tonnes of query functions.
Mysql 5.7 引入了 JSON 数据类型，它提供了大量的查询功能。
Since there isn't a compatible resultset function, how and what to i do use retrieve the data stored in this datatype.
由于没有兼容的结果集函数，我如何以及如何使用检索存储在此数据类型中的数据。
采纳答案by YCF_L
It should be rs.getString, because getStringused with VARCHAR, TEXT, we can consider JSonlike a Stringtype, so you can get the result, using getString.
应该是rs.getString，因为getString与VARCHAR, 一起使用TEXT，我们可以认为JSon是一个String类型，所以可以得到结果，使用getString.
Simple Example
简单示例
Double check with MySQL 5.7 and PostgreSQL 9.4 :
仔细检查 MySQL 5.7 和 PostgreSQL 9.4 ：
MySQL 5.7 SQL
MySQL 5.7 SQL
create database db_test;
create table table_test(json JSON);
INSERT INTO table_test VALUES('{"key1": "value1", "key2": "value2"}');
CODE
代码
public static void checkJSon() {
try {
Class.forName(DRIVER);
Connection connection = DriverManager.getConnection(DB_URL, DB_username, DB_password);
String q = "SELECT * FROM table_test";
PreparedStatement preparedStatement = connection.prepareStatement(q);
preparedStatement.execute();
ResultSet rs = preparedStatement.executeQuery();
while (rs.next()) {
System.out.println(rs.getString("json"));
}
} catch (ClassNotFoundException | SQLException e) {
e.printStackTrace();
}
}
It print to me :
它打印给我：
{"key1": "value1", "key2": "value2"}
