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  • JDBC 数据库连接 Java操作数据库 jdbc快速入门

    JDBC基本概念 
         Java DataBase Connectivity  数据库连接  java操作数据库
    本质上(sun公司的程序员)定义的一套操作关系型数据库的规则 既接口
    

     更新内容之前

    代码

     1 package cn.zmh.JDBC;
     2 
     3 import java.sql.Connection;
     4 import java.sql.DriverManager;
     5 import java.sql.Statement;
     6 /*JDBC */
     7 public class Demo11JDBC {
     8     public static void main(String[] args) throws Exception {
     9         /* 1: 导入jar包 mysql-connector-java-5.1.37-bin
    10                  1.1复制mysql-connector-java-5.1.37-bin到项目的libs目录下
    11                  1.2  右键----》Add As Library
    12          */
    13         // 2 注册驱动
    14         Class.forName("com.mysql.jdbc.Driver");
    15         // 3 获取数据库连接对象  Connection
    16         Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/qy97","root","root");
    17         // 4 定义sql语句    UPDATE 表名 SET 列名='修改的字段' WHERE 键值
    18         String sql1 = "UPDATE user1 SET unames='张三'   WHERE uid=1";
    19         String sql2 = "UPDATE user1 SET unames='李四'   WHERE uid=2";
    20         String sql3 = "UPDATE user1 SET unames='王五'   WHERE uid=3";
    21         String sql4 = "UPDATE user1 SET unames='赵六'   WHERE uid=4";
    22         String sql5 = "UPDATE user1 SET uaddress='北京' WHERE uid=1";
    23         String sql6 = "UPDATE user1 SET uaddress='上海' WHERE uid=2";
    24         String sql7 = "UPDATE user1 SET uaddress='广州' WHERE uid=3";
    25         String sql8 = "UPDATE user1 SET uaddress='深圳' WHERE uid=4";
    26         // 5 获得执行sql语句对象    Statement
    27         Statement statement = connection.createStatement();
    28         // 6 执行sql语句
    29         int i1 = statement.executeUpdate(sql1);
    30         int i2 = statement.executeUpdate(sql2);
    31         int i3 = statement.executeUpdate(sql3);
    32         int i4 = statement.executeUpdate(sql4);
    33         int i5 = statement.executeUpdate(sql5);
    34         int i6 = statement.executeUpdate(sql6);
    35         int i7 = statement.executeUpdate(sql7);
    36         int i8 = statement.executeUpdate(sql8);
    37         // 7 控制台输出结果   可以不写
    38         System.out.println(i1+""+i2+""+i3+""+i4+""+i5+""+i6+""+i7+""+i8);
    39         // 8 释放资源
    40         statement.close();
    41         connection.close();
    42 
    43     }
    44 }

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  • 原文地址:https://www.cnblogs.com/zhangmenghui/p/10629698.html
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