练习1
借助循环,向数据库中插入100条数据,并在mysql-front中观察查询结果
1 package jdbc; 2 3 import java.sql.Connection; 4 import java.sql.DriverManager; 5 import java.sql.SQLException; 6 import java.sql.Statement; 7 8 public class TestJDBC { 9 public static void main(String[] args) { 10 // 初始化驱动 11 try { 12 Class.forName("com.mysql.jdbc.Driver"); 13 } catch (ClassNotFoundException e) { 14 // TODO Auto-generated catch block 15 e.printStackTrace(); 16 } 17 // 使用try-with-resource的方式自动关闭连接,因为Connection和Statement都实现了AutoCloseable接口 18 try ( 19 Connection c = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/how2java?characterEncoding=UTF-8", 20 "root", "admin"); 21 Statement s = c.createStatement();) { 22 s.execute("truncate table hero"); 23 String name = null; 24 float hp = 100.0f; 25 int damage = 100; 26 for (int i = 0; i < 100; i++) { 27 name = "\'" + "Hero-" + String.valueOf(i + 1) + "\'"; //注意格式,必须单引号' 28 String sql = "insert into hero values(null," + name + "," + (hp++) + "," + (damage++) + ")"; 29 s.execute(sql); 30 } 31 } catch (SQLException e) { 32 // TODO Auto-generated catch block 33 e.printStackTrace(); 34 } 35 36 } 37 }
效果图: