初识JDBC

package forJDBC;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class First {

	public static void main(String[] args) throws ClassNotFoundException, SQLException {
		
		String driver = "com.mysql.jdbc.Driver";//驱动程序名
		Class.forName(driver);//加载驱动程序
		
		String url = "jdbc:mysql://localhost:3306/lin";//URL指向要访问的数据库名lin
		String user = "root";//MySQL配置时的用户名
		String password = "usbw";//java链接MySQL配置时的密码
		//链接数据库，暂时理解，con为数据库和编译器之间的一个链接
		Connection con = DriverManager.getConnection(url, user, password);
		//st作为链接中的一个工具，用来执行SQL语句
		Statement st = con.createStatement();
		//列出几个要执行的语句
		String delSql = "delete from student";
		String insertSQL = "insert into student values (1,'lins',18)";
		String insertSQL2 = "insert into student values (2,'linS',18)";
		//执行
		st.execute(delSql);
		st.execute(insertSQL);
		st.execute(insertSQL2);
		
		String delSql2 = "delete from student where id = 2";
		//statement里的executeUpdate方法执行语句后返回被此语句影响的行数
		int r = st.executeUpdate(delSql2);
		if(r>0)
			System.out.println("SUCCESS!");
		
		String selectSql = "select * from student";
		//executeQuery方法返回一个结果集 ，通常执行select类型语句，最常用的方法
		ResultSet rs = st.executeQuery(selectSql);
		
		//输出结果集
		while(rs.next()) {
			int id = rs.getInt("id");
			String name  = rs.getString("name");
			int age = rs.getInt("age");
			System.out.println(id+" "+name+" "+age);
		}
		
	}

}