java 串連資料庫

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java環境是：

jdk1.8    java version "1.8.0_171"

1.安裝mysql的jar

：http://dev.mysql.com/downloads/connector/j/

我下載的時候，一直打不開，開了藍燈很快就開啟了。藍燈有時候不可以用

jar支援的版本：

 

下載完成後，需要eclipse加入jar包：即可把jar包放進項目裡

 

2.建立資料庫：

CREATE TABLE `student` (  `id` int(11) NOT NULL,  `name` varchar(255) DEFAULT NULL,  `age` int(11) DEFAULT NULL,  PRIMARY KEY (`id`)) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4;

3.編寫java代碼

package test;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class MysqlDemo {    final static String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";    final static String DB_URL = "jdbc:mysql://localhost:3306/mv?serverTimezone=UTC";    final static String USER = "root";    final static String PASS = "root";    public static void main(String[] args)            throws ClassNotFoundException, SQLException {        Connection conn = null;        Statement stmt = null;        Class.forName(JDBC_DRIVER);        System.out.println("串連資料庫...");        conn = DriverManager.getConnection(DB_URL, USER, PASS);        // 執行查詢        stmt = conn.createStatement();        String sql = "select * from student";        ResultSet rs = stmt.executeQuery(sql);        // 展開結果集        while (rs.next()) {            int id = rs.getInt("id");            String name = rs.getString("name");            int age = rs.getInt("age");            System.out.println("ID:" + id);            System.out.println("name:" + name);            System.out.println("age:" + age);        }    }}

執行結果：成功

 

4.遇到的問題：

4.1 The server time zone value ‘?й???????‘ is unrecognized or represents more than one time zone

解決：

jdbc:mysql://localhost:3306/mv?serverTimezone=UTC

4.2 Loading class `com.mysql.jdbc.Driver‘. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver‘. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary

解決：原來的driver有修改

final static String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";

 

java 串連資料庫