使用 mysql-connector-java.jar
// 删除
public void test01() throws ClassNotFoundException, SQLException {
//1.注册驱动
Class.forName("com.mysql.jdbc.Driver");//jar 5.1
Class.forName("com.mysql.cj.jdbc.Driver");//jar 8
//2.创建数据库连接
String url = "jdbc:mysql://localhost:3306/jgs1904?useSSL&serverTimezone=GMT%2B8";
String user = "root";
String password = "root";
Connection conn = DriverManager.getConnection(url, user, password);
//3. 编写sql语句
String sql = "delete from user where id = 1";
//4. 创建sql语句执行者
Statement stmt = conn.createStatement();
//5. 执行sql语句
int result = stmt.executeUpdate(sql);
System.out.println(result);
//6. 释放资源
stmt.close();
conn.coose();
}
//查询
public void test02(){
//---获取数据库连接conn
Statement stmt = conn.createStatement();
//执行sql语句
ResultSet rs = stmt.executeQuery("select * from user");
//获取结果集的数据
while(rs.next()){
long id = rs.getLong("id");
String username = rs.getString("username");
String pwd = rs.getString("password");
}
//释放资源
rs.close();
stmt.close();
conn.close();
}
//批处理
//---获取数据库连接conn对象
Statement stmt = conn.createStatement();
//添加批处理语句
stmt.addBatch("delete from user where id = 2");
stmt.addBatch("insert into user values(null, 'user', 'user')");
stmt.addBatch("update user set username = 'root' where id = 3");
//执行批处理语句
int[] result = stmt.executeBatch();
for(int i : result) {
System.out.println(i);
}
stmt.close();
con.close();