JDBC連接配接MySQL并且查詢操作。

1 package com.imooc.db;
 2 
 3 
 4 import java.sql.Connection;
 5 import java.sql.DriverManager;
 6 import java.sql.ResultSet;
 7 import java.sql.SQLException;
 8 import java.sql.Statement;
 9 
10 
11 
12 public class DBUtil {
13     private static final String URL="jdbc:mysql://127.0.0.1:3306/test";
14     private static final String USER="root";
15     private static final String PASSWORD="****";
16     public static void main(String[] args)throws Exception{
17 
18     //1.加載驅動程式
19     Class.forName("com.mysql.jdbc.Driver");
20     //2.獲得資料庫的連接配接
21     Connection conn=DriverManager.getConnection(URL, USER, PASSWORD);
22     
23     Statement stmt = conn.createStatement();
24     ResultSet rs= stmt.executeQuery("select * from tb3");
25     float sum=0;
26     while(rs.next())
27     {
28         sum +=rs.getFloat("salary");
29         System.out.println(rs.getString("username"));
30     }
31     System.out.println(sum);
32     
33     
34 }
35 }      

轉載于:https://www.cnblogs.com/vector11248/p/5487140.html