当前位置:Gxlcms > 数据库问题 > Java操作MySQL数据库模板

Java操作MySQL数据库模板

时间:2021-07-01 10:21:17 帮助过:23人阅读

#日常分享所得,欢迎关注哦~#

本模板非常适用于正在学习计算机专业的大学生,在做课程设计时,难免会遇到需要使用到数据库的情况。这里强烈推荐使用MySQL数据库,为什么呢?简单说,社会上大部分的大中小型网络公司都在使用MySQL,成本低是一个很大的原因!

本模板主要是对MySQL数据库进行增删改查操作

主要版本号:

  • mysql-connector-java-8.0.19

  • mysql-8.0.20-winx64

添加数据

  1. package com;
  2. ?
  3. import java.sql.Connection;
  4. import java.sql.DriverManager;
  5. import java.sql.Statement;
  6. ?
  7. public class Insert {
  8. public static void main(String[] args) throws Exception {
  9. Class.forName("com.mysql.cj.jdbc.Driver"); //抛出异常,写法是固定的
  10. String url = "jdbc:mysql://localhost:3306/class?useUnicode=true&characterEncoding=utf8&useSSL=true&serverTimezone=UTC";
  11. String username = "root"; //数据库账户名
  12. String password = "123456"; //数据库登录密码
  13. Connection connection = DriverManager.getConnection(url, username, password);
  14. Statement statement = connection.createStatement(); //statement来执行sql的对象
  15. String sql = "INSERT INTO `student`(`name`,`pwd`,`sex`,`birthday`,`address`,`email`,`gradeid`)\n" +
  16. "VALUES(‘yfl‘,‘9933‘,‘女‘,‘1999-02-13‘,‘xiapu‘,‘102065@qq‘,‘2‘)";
  17. int num = statement.executeUpdate(sql); //执行完sql后返回受影响的行数
  18. if(num>0)
  19. System.out.println("插入成功!");
  20. statement.close();
  21. connection.close();
  22. }
  23. }
  24. ?

删除数据

  1. package com;
  2. ?
  3. import java.sql.Connection;
  4. import java.sql.DriverManager;
  5. import java.sql.Statement;
  6. ?
  7. public class Delete {
  8. public static void main(String[] args) throws Exception {
  9. Class.forName("com.mysql.cj.jdbc.Driver");
  10. String url = "jdbc:mysql://localhost:3306/class?useUnicode=true&characterEncoding=utf8&useSSL=true&serverTimezone=UTC";
  11. String username = "root"; //数据库账户名
  12. String password = "123456"; //数据库登录密码
  13. Connection connection = DriverManager.getConnection(url, username, password);
  14. Statement statement = connection.createStatement(); //statement来执行sql的对象
  15. String sql = "DELETE FROM `student` WHERE id=5";
  16. int num = statement.executeUpdate(sql); //执行完sql后返回受影响的行数
  17. if(num>0)
  18. System.out.println("删除成功!");
  19. statement.close();
  20. connection.close();
  21. }
  22. }

  

  1. <span><span class="cm-keyword"><span class="cm-def"><span><span><span><span class="cm-keyword"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span><span class="cm-keyword"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span><span class="cm-keyword"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span><span><span><span class="cm-keyword"><span class="cm-keyword"><span class="cm-def"><span><span class="cm-keyword"><span class="cm-keyword"><span class="cm-variable-3"><span class="cm-variable"><span class="cm-variable-3"><span class="cm-variable"><span class="cm-keyword"><span class="cm-variable"><span><span class="cm-variable"><span class="cm-variable"><span class="cm-string"><span><span class="cm-variable-3"><span class="cm-variable"><span class="cm-operator"><span class="cm-string"><span><span class="cm-variable-3"><span class="cm-variable"><span class="cm-operator"><span class="cm-string"><span class="cm-comment"><span><span class="cm-variable-3"><span class="cm-variable"><span class="cm-operator"><span class="cm-string"><span class="cm-comment"><span><span class="cm-variable"><span class="cm-variable"><span class="cm-operator"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span><span class="cm-variable"><span class="cm-variable"><span class="cm-operator"><span class="cm-variable"><span class="cm-variable"><span class="cm-comment"><span><span class="cm-variable-3"><span class="cm-variable"><span class="cm-operator"><span class="cm-string"><span><span class="cm-variable-3"><span class="cm-variable"><span class="cm-operator"><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span class="cm-comment"><span><span class="cm-keyword"><span class="cm-variable"><span class="cm-operator"><span class="cm-number"><span><span class="cm-variable"><span class="cm-variable"><span class="cm-variable"><span class="cm-string"><span><span class="cm-variable"><span class="cm-variable"><span><span class="cm-variable"><span class="cm-variable"><span><span><br><span><span>?</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

更新数据

  1. package com;
  2. ?
  3. import java.sql.Connection;
  4. import java.sql.DriverManager;
  5. import java.sql.Statement;
  6. ?
  7. public class Update {
  8. public static void main(String[] args) throws Exception {
  9. Class.forName("com.mysql.cj.jdbc.Driver"); //抛出异常,写法是固定的
  10. String url = "jdbc:mysql://localhost:3306/class?useUnicode=true&characterEncoding=utf8&useSSL=true&serverTimezone=UTC";
  11. String username = "root"; //数据库账户名
  12. String password = "123456"; //数据库登录密码
  13. Connection connection = DriverManager.getConnection(url, username, password);//需要抛出异常,"connection"就可以代表数据库了
  14. Statement statement = connection.createStatement(); //statement来执行sql的对象
  15. String sql = "UPDATE `student` SET `name`=‘atm‘ WHERE `id`=3";
  16. int num = statement.executeUpdate(sql); //执行完sql后返回受影响的行数
  17. if(num>0)
  18. System.out.println("更新成功!");
  19. statement.close();
  20. connection.close();
  21. }
  22. }

  

查询数据

  1. package com;
  2. ?
  3. import java.sql.*;
  4. ?
  5. public class Select {
  6. public static void main(String[] args) throws ClassNotFoundException, SQLException {
  7. //第一步:加载驱动
  8. Class.forName("com.mysql.cj.jdbc.Driver"); //抛出异常,写法是固定的
  9. //第二步:验证用户信息和url
  10. String url = "jdbc:mysql://localhost:3306/class?useUnicode=true&characterEncoding=utf8&useSSL=true&serverTimezone=UTC";
  11. String username = "root"; //数据库账户名
  12. String password = "123456"; //数据库登录密码
  13. //第三步:连接成功后获得数据库对象
  14. Connection connection = DriverManager.getConnection(url, username, password);//需要抛出异常,"connection"就可以代表数据库了
  15. //第四步:获取执行sql的对象
  16. Statement statement = connection.createStatement(); //statement来执行sql的对象
  17. //第五步:使用sql的对象去执行sql语句
  18. String sql = "SELECT * FROM `student`";
  19. ResultSet resultSet = statement.executeQuery(sql); //执行完sql后返回一个结果集resultSet,这个结果集已经封装了全部查询出来的结果
  20. /*
  21. statement.executeQuery();//查询操作,返回ResultSet
  22. statement.execute();//可以执行任何SQL
  23. statement.executeUpdate();//更新、插入、删除都用它,返回一个受影响的行数(int)
  24. */
  25. while (resultSet.next()){ //对结果进行打印
  26. System.out.println("id="+resultSet.getObject("id"));
  27. System.out.println("name="+resultSet.getObject("name"));
  28. }
  29. //第六步:使用完毕,释放数据库的连接
  30. resultSet.close();
  31. statement.close();
  32. connection.close();
  33. //释放连接尽量遵循先创建后释放的原则
  34. }
  35. }

  

事实上,这样的模板更适用于操作量小的工程项目,不利于代码的整洁化,接下来小编将会把这些代码进行封装,在使用时只需要调用封装的接口即可。

#日常分享所得,欢迎关注学习计算机、热爱计算机的我!后续更精彩#

Java操作MySQL数据库模板

标签:fence   div   date()   释放   cti   password   root   lock   小型   

人气教程排行