1 package com.lovo; 2  3 import java.sql.Connection; 4 import java.sql.DriverManager; 5 import java.sql.ResultSet; 6 import java.sql.SQLException; 7 import java.sql.Statement; 8  9 public class Test {10     public static void main(String[] args) {11         Connection con = null;12         try {13             Class.forName("com.mysql.jdbc.Driver");//加载驱动14             //jdbc:mysql://是驱动协议，就像http：//一样15             con = DriverManager.getConnection("jdbc:mysql://localhost:3306/company", "root", "111");//创建连接16             Statement stmt = con.createStatement();//创建语句17             String sql = "SELECT emp.* from emp INNER JOIN " +18             " (select DISTINCT emp.sal as sal from emp where job <> ‘总裁‘ order by emp.sal desc limit 0,3) as t1 "+19             " on emp.sal=t1.sal order by emp.sal";20             ResultSet rs = stmt.executeQuery(sql);//发送sql语句得到结果集（游标）21             while (rs.next()) {22                 System.out.println("姓名：" + rs.getString("ename") + "\t工资：" + rs.getString("sal"));23             }24         } catch (ClassNotFoundException e) {25             e.printStackTrace();26         } catch (SQLException e) {27             e.printStackTrace();28         }finally{29             if (con != null) {30                 try {31                     con.close();32                 } catch (SQLException e) {33                     e.printStackTrace();34                 }35             }36         }37     }38 }

 1 package com.lovo; 2  3 import java.sql.Connection; 4 import java.sql.DriverManager; 5 import java.sql.PreparedStatement; 6 import java.sql.ResultSet; 7 import java.sql.SQLException; 8  9 10 public class Test02 {11     public static void main(String[] args) {12         Connection con = null;13         try {14             Class.forName("com.mysql.jdbc.Driver");15             con = DriverManager.getConnection("jdbc:mysql://localhost:3306/company", "root", "111");16             String sql = "insert into dept value(?,?,?)";17             con.setAutoCommit(false);//设置事物部自动提交18             PreparedStatement ps = con.prepareStatement(sql);19             for (int i = 0; i < 5; i++) {20                 ps.setInt(1, i);21                 ps.setString(2, "科研部" + i);22                 ps.setString(3, "四川成都");23                 ps.addBatch();24             }25             int[] infl = ps.executeBatch();26             con.commit();//提交事物27             for (int i : infl) {28                 System.out.print(i + "  ");29             }30         } catch (ClassNotFoundException e) {31             e.printStackTrace();32         } catch (SQLException e) {33             try {34                 con.rollback();//回滚事物35             } catch (SQLException e1) {36                 e1.printStackTrace();37             }38             e.printStackTrace();39         }finally{40             if (con != null) {41                 try {42                     con.close();43                 } catch (SQLException e) {44                     e.printStackTrace();45                 }46             }47         }48     }49 }