java-jdbc-mysql：实现数据库表的增删改查

以数据库test下数据表student（sno，sname，ssex，sage，sdept）为例：

student表中的已有的所有记录：

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USmos4rvKjGgROqcpJqH9n2wwE8tSkhF7jGGneYtBhD7gY6FZXCEXomrevmPTfl1EZi8fDfyGOw0FhMaro0f0ARCkIeKK4lsC1lULU1R9Xi3F82sVCNXZlZky6XgDyuF532utObxm9+6uyDGySavNU15gQwKOAJN2FWDEW54Y+JF6EztXVoOVKmmQrSnTjkjpHFiTGlZu4tiAP6nVNeF0Tyf0dUxR7N1UlzsU8lM8Mcq6uBgNX/v2yIgMf0Y1zN/VgMa4tyIN6XWmva8LsuYwnoHoIHlf5QfoP1aPrB7lwvH1gLuwWWAU8XUtDFP1WNMQYK8Z6UPk3i2sL8rhe14TXNb61suXvMgwduuWrunBPoOXFqIRJGF7nhNc5vrWy9ZNT3GUso3puIiUwMaXuLO6Pt6qncKNhUHidE17nxNbKNneZggJ+8uLseIc+Z+FGw4TDXcYxZq+YGCbBcJehQ/qaSPflT+yNRuu1HsNI4C7jhkR3Gfwtw0jgLuMGaZdJxBHlLsNERdpl8M+Egd+SSB/CjEujAM7FKdKRUDH4A6NlHJAkbTeAJClaoVVRtIzpxNjSaeZfGlE3Lt5e5d9NPmFVlAEidBm/meraf4sZV20APIK3h2MhiVJV+SUbxLWF1sLFZAK3diGtfnydGLhyE9cW5EHHOsbHOsY3l7fOnXr7FzmRUTGn13/G8OMBG2BXxHH8LhonFz9RNIuynbZKQWvhYjIpJKlCU/jXrROkQ2NjKzUZBfKgox3jI+3e5vLWuZPaXcaPNFOB7VSNq/zgR8weNU4ufqLfzANRzcKM66K1cFi2LUnRdUZ3blwbEY2p0xgKuYCRdm+4bWxjafPsSfPvMAiozN96suYijqv8qAbhKgdSJtVJelqk8qTjyImxUyAyogMUD3VJAHEpIsbPUOvIUOvIxtLmmbKz+UGtBcNdICV0GXEcDgqLUUWP7gcAbyyWrHihmhg6YkyUgnZ5EkgPHuBcN66t4iFdLwB53IHmoYHmobXFjYoTb7/1TfcUSQf9x8nb3WXEucapFx8FJOkuxIpxforqInQKxlhXjNb+hmJRm5lOu85140YsHuRBoIM8aH/jwL3GgbWFtQ+OV+hGVWUnMD1/ixmH9yA0lpa98e4a7Ionay6wE7ylLsZVJZ1FV6Ck1a9ybra5UYrHuA5tQR70bsPA3fr+F7m106Zdxo/qIXhc5QfpP1SPrh/kwvH2KfVTGMCPakp0DPQDMqzL83umcI6pBwOHuqEx424gj3uvYeBeff9abtdzGcY6gZYRqGz3enTBdEOGkdPfNNjfdH9tcZ27DAXSniIey7wZHkcLAF9ZpLjFMBgGW4YHW4bXd7/7y1hEfG4cjw59QttZgtbCxMlQ2+hQ22jgN9kMI4XbCmPCcNvo60/lnSkz/1Qes0fgLsOYcL915H7ryPrSZgU/l2HC4C7DmNDfONjfOLi2wO/+MuFwl2FM6K3uu13dt5p9/v7R8vyg3d//i79hgcelUQDn4hTpSKhOxHJ3zcLbq8QYe4iIWXT3gumyFEs9SGte1wkF5KHbb3S23+hcml0pO3xSN6rfTHXtv8WMqzYeHsHbIzXDRN+VGEsKH93TIUadUdy6rAd/rgJ5o84kRhhhgIavGuu/asw9WygtOa4bFb9bnqKbqMYDNh6uy2DsMddaCzcjrnqKEl3MqiU5UESKKHHVgycjSlxbkAetulBddaF67sn8kX1Ho0SVZkqVzcC4yg9+xOxR91UlepCOA4PSVEhdRdcfmBI6Yh0DnbZCuKkHceMcLFkljDDA13+8ce3z6zOPZw++e8jYCXCEUrITpToV0tUCRwtpb+wqItKcBOKqBKsqD3NNgVQhXTg3qJJGlExV/bvcx3i48tm1y59dm340c+Cdg/lBraXCRzclZFN1usy2XBVdy4/u1ka3VxWWtxuMsYEkA/2hIxTo6rTi3CAocoqq4D0BrejRIQ969bOvL//hqnGXkVqqDgny8GBCAI8CkrRWARAxPynF2jHJMUhgFP0qe9qiVMel9mwWETkrYBa6784gD3rt8+tX/+/rmW9mD/747Ssmg6wBmZJmUzUuLWhghMI+FOOqgiVh8inNYR67+lWzDOaaYaZTyy0yz3iHeLPQfXcGedCbf666/qebs0/mDu07rBvVE1A9BI+r/CD9h+rB+EGkKrhwpBmgR/Tmf0i8AEJrrcJgyVbmFkgsgzqxojNgprW/pJAHrblYV3OxLvs0e3T/McIwDAGOqzP2w8AklaarLU1XWxZnFo8fPBG3FkYbgx+8xlGk43RBmeKh/WZX+82u5bldn/1lmNeE9i9uNEw4PdW9PdW9q9nnp46+H7eWPQEfS2bP0Vd7t6/27vPsi/Jj5eHWTGQS12XE90TN3iJl9i536u/dqbv3IrdWfux03FqKkNAjWvgHNSAPvmUYCXcb+l9/U0p5KXcZchLRVgJwl2Gicq9x8F7D4NrC+unSD/KD+JOg+oGs+lmNGZdGAZyLU6QjWjphzDqF5/tIW7yH02CxAAWi08Cz43oImMG3LiEPPdgyNNgytL64kdDvloRVmekMxWBX/EEDF+7RPUL4W7sQVX9c9eC9IXDtv42lKsjjDrWODrWObixtGnxPNma3xMxixgM2YmVL5WG2CqMzFK1dCRh7RnVsF139+Fu7EOVHt261HIaaBQA0OIM86GiHN9rhbS5v+b8pxSCqNFOqbAbGVX7wI2aPYvQYhIDNgCV7OmB0RtTvNyZSYlFn9BBu6kHMnlSDS8iDel1pr2tia2X77Enzb0oJqPSnLyVsnjiu8qMahKtclTLRPlSPRVQVljgSKluK43oIPRcUQQuCie7MeHd6a2X7nK/LaC0V7gIpIZvS5AJBYTGq6Bh7WA9A9FKIt5Ki6HepnPTI4evWwBXGTHouSJeMFGaf8e7MRHfGuMtILQPJErMpzgUiwmJUtYKxB/TARNwV92UkCtBaaSix67TimboeAmb5W7OgFiEP6nWlva504BWTQdaATEmzqRoXQ8MjUexVekLRyg8STFxbGEeUzqITT5SZeOtBvAU0uIE86Ei7N9Ju+O4vcFS0xlV+kP519QBLCF2yfxbSWJxrNtEiZvpVU+hWFCXPoW4xJWRXpzRWai90mYHmoYHm4OdlGDoKocsYAMhO6IoYd/TV3btTd/d5bo3/tyQ1+R9cMevQRPWDLqHLYWKg42Z3Z2XPytzqycOn4tZS/CTrTIY+kU7WcpjYaLrW2nytdXFmif9WnhsSfTITLZ6JjdpLDbWXGnLPFo6WlMatZU+Q6IOaaPFMbFR/UXfri9rs0+yR946GWzOaiL/OkBK3TCwJksoUENUXa299UTP/bfbwviNxayl+MG2lkFsSdxnGhNpL9bUX67NPc/7nMvhqVlW/6mBgxqVRAOfiFOkI3n8oZqfd8/1SJvZmYazfJXRdVbduMd60ggKHgm7VsDDCAE1XWhquNOWeLfi/j0kra/C1/xYzrtp4eARvr+sNGQIzRXXhHq39RRKjzihugdrARzewhGM5rg26HfwHHTe62q53LM0slx44rhsVs1v+KsSPB2w8XF9Q2cOaDVKsNQUoIPLdVWAWV9wFS3KgiBRRdOtWy2H00O4hj95be+d2dd/K/GrZobffxxTx4OWvA8dYNa7ygx+J8mjExeqaYZZMjdmSQ0es4yAzmLrVcmIQTrxGSbcHeZ4Hm+7faxx4kVuL8n1MAZX+3UoJmyeOq/yoBr3dhNoHZiHt7eLJoA5qEWneYtBhFWTdEkUUr5NYGChGOsaG2kbWFzfN/rq41DiQr8CFOA4HhcWootuyRzrRJd5K0tUvGrvRT3rk8HVr4ApjCVxjXFmENM+pVCo10Z3xOic2V7Yq9P+6uMrSv1UpWZcR5wIR7XYNXXsDSZjpxnOtoKtfmjSrirBxST0D9WngLdTSLBYF5NEztydf/xWrihOGf/kBvk4JXQYex3QBavtQtPKDREtARMwi+vfLtqKQiHRugdrARzewhGMloh40yPRNZW5Pbq/u7MG/LwPYYxaONBbnwm6RmEX3B3I/t0BiIevEej0gg7rMsF8AYYAHfQ8f9D7c2d1lGDocF5BF/LXo/iQwCeZB79SD3qmd59xlyPHcvtywiKqnJHEtTAxk+iYzfZPcZdyQuGMZ+pwlcStiYiDTO5npneRXTAzDUJHpfZDpfcDPZRiGoSLdm073Zraf71SUnQm3ZhiG0SXdMzFxe2J7dbviBHcZhmEI8LpGx7rHNle2+JtSGIYhYbh9cLh9aHN5s7z0dNxaGIYpRu413+5vvru2uHbq6NvvY+LPXMEkPT9J0c863UCuv7u2vaeuazX3vOxwpL8vs6dIen6Sop91uoFcf+uN+rbKluX5ldKDJ1KK/+IhDu7N8aTnJyn6WaebcZV++9RdqWy4Vrc4u3i0RPsvcu5Zkp6fpOhnnW4g13/z4tfVX1XnphcO73/7rW9Jzxo1Sc9PUvSzTjeQ6//6wpXKLyuz07nDvu8wYBiGsca1C1cqL1ZlpxeO7OdvsGUYhoCvL1yr+rI6N7PrfRmGYRhr3PjiRs1XtQszi8cOnIhbC8MwxUjVxaq6Kw2Ls8vHD5XFrYVhmGKk+lJ1w9XGpTnuMgzD0FBzqabxatPy3PIJ7jIMw1BQc6mm8UrT0uzy8YP8vgzDMATculhdf7lhcWap9AD/jolhGAKqvqiqvVS3ML14rKQU+P8OhUnhK8wTkKqbZJV9XJuVoMwz8VN14VbNl3UL0wtHS45JKzg2ZQhiUWgQEU5s6CpU9vHuV+GXB1MoVH9RU3epfnFm8VgCu4x7DHIiTvGPYJ6GqOx1/ViHK4RB0XC5selqy9Lssvi+DLL6gZ+r+J/hUntMaFXQKH6Q/jEhpGaBpIW6Utnr+tFdL8YzMg/MnqbtRkdnZdfK/GrgN9m6p0ha/cC1OFcrLuwQ6QejEwhhoDAwKC4fduLJmouBn4jXoQtkmF301vbdqbv7YmHt1JFT+UF86XhvSCG6BnAqzIo1MMvAodTME4Dto/jH+FTZ6/rB6NHNodnGMXuLweb791uGNpY2yo/946+La9UNULXAtepURDzDuicE4we2NHCe8p1qpE+VvUFTkFqqJiKFYSIye5qxDm+sc3zL900pUc6nOKgqaJWNre6A8YPRgNEfRafqFmMPm8EyolwjwzHMP5joSadvZ7ZXd/Lf+oavHs8H8iH4hJiFlvpEuoJ1wkvD6AzMUukP9a+yB/wAMvDrhcdDwzFMKpVKZfomM32T/D3ZDMNQMXlnavLO1M6L786e5C7DMAwBk3cfTt55uPPiu7Mnz8WthWGYYmTyTr7L8HMZhmEImOzjLsMwDCWTfQ9fvy/D7/4yDEPCZN/Ug76pnefcZRiGoeFB31Smd3Jndaei7EzcWhiGKUL+HwTSk1ObHW3ZAAAAAElFTkSuQmCC" alt="" />

Java代码对表test.student的操作：

创建student类，包含String sno，String sname，String ssex，int sage，String sdept：

 package jdbcTest;

 public class Student {
     private String sno,sname,ssex,sdept;  //学号，姓名，性别，部门
     private int sage;  //年龄

     public Student(){}

     public Student(String sno,String sname,String sex,String dept,int age){
         this.sno = sno;
         this.sname = sname;
         this.ssex = sex;
         this.sdept=dept;
         this.sage = age;
     }

     public void setSno(String sno){
         this.sno = sno;
     }

     public String getSno(){
         return this.sno;
     }

     public void setSname(String sname){
         this.sname = sname;
     }

     public String getSname(){
         return this.sname;
     }

     public void setSsex(String sex){
         this.ssex = sex;
     }

     public String getSsex(){
         return this.ssex;
     }

     public void setSdept(String dept){
         this.sdept = dept;
     }

     public String getSdept(){
         return this.sdept;
     }

     public void setSage(int age){
         this.sage = age;
     }

     public int getSage(){
         return this.sage;
     }

     public String toString(){
         return this.sno+" "+this.sname+" "+this.ssex+" "+this.sage+" "+this.sdept;
     }
 }

创建StudentDA类，用于数据库连接、操作数据库：

 package jdbcTest;

 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.ArrayList;
 import java.util.List;

 public class StudentDA {
     String driverName = "com.mysql.jdbc.Driver"; // 加载JDBC驱动
     String dbURL = "jdbc:mysql://localhost:3306/test"; // 连接服务器和数据库sample
     String userName = "test"; // 数据库用户名
     String userPwd = "test"; // 数据库密码
     static Connection dbConn = null;  //连接信息
     Statement statement;   //sql语句
     PreparedStatement pstatement;
     ResultSet rs;      //结果集

     //数据库连接
     public Connection dBConnection(){
         try {
             Class.forName(driverName);
             dbConn = DriverManager.getConnection(dbURL, userName, userPwd);
             System.out.println("Connection Succeed!");
         } catch (Exception e) {
             System.out.println("Connection failed!");
             e.printStackTrace();
         }
         return dbConn;
     }

     //查询记录,将查询结果放在list中
     public List<Student> selectAllStudent(){
         List<Student> studentList = new ArrayList<Student>(); //存放查询结果
         String sql = "select * from student"; 

         try{
             statement = dbConn.createStatement();
             rs = statement.executeQuery(sql);  //执行sql语句并返回结果集
             while (rs.next()) {
                 Student student = new Student();
                 student.setSno(rs.getString("sno"));
                 student.setSname(rs.getString("sname"));
                 student.setSsex(rs.getString("ssex"));
                 student.setSdept(rs.getString("sdept"));
                 student.setSage(rs.getInt("sage"));
                 studentList.add(student);  //将查询出的student信息放入studentList链表中
             }
         }catch(Exception e){
             e.printStackTrace();
         }
 /*        finally{
             try {
                 statement.close();
                 dbConn.close();
             } catch (SQLException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
             }
         }*/
         return studentList;
     }

     //插入一个学生记录,如果插入成功，返回true
     public boolean insertStudent(Student stu){
         int i = 0;
         String sqlInset = "insert into test.student(sno,sname,ssex,sage,sdept)" +
     " values(?, ?, ?, ?,?)";   //插入语句

          try {
             pstatement = dbConn.prepareStatement(sqlInset);
             pstatement.setString(1, stu.getSno()); //设置SQL语句第一个“？”的值
             pstatement.setString(2,stu.getSname());
             pstatement.setString(3,stu.getSsex());
             pstatement.setInt(4, stu.getSage());
             pstatement.setString(5,stu.getSdept());
             i = pstatement.executeUpdate();  //执行插入数据操作，返回影响的行数
             if(i == 1){       //如果插入数据成功，则影响的行数为1
                 return true;
             }
         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
         return false;
     }

     //根据sno删除记录
     public boolean deleteStudent(String sno){
         int i = 0;
         String sqlDelete = "delete from test.student where sno = " + sno; 

         try {
             pstatement = dbConn.prepareStatement(sqlDelete);
             i = pstatement.executeUpdate();  //执行删除数据操作，返回影响的行数
             if(i == 1){       //如果删除数据成功，则影响的行数为1
                 return true;
             }
         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
         return false;
     }

     //删除所有的记录
     public void deleteAll(){
         String sqlDeleteAll = "delete from student";
         try {
             pstatement = dbConn.prepareStatement(sqlDeleteAll);
         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
     }

     //根据学号sno，更新学生年龄sage
     public boolean updateStudent(String sno,int age){
         int i =0;
         String sqlUpdate = "update test.student set sage=? where sno=?";
         try {
             pstatement = dbConn.prepareStatement(sqlUpdate);
             pstatement.setInt(1,age); //设置SQL语句第一个"?"的参数值
             pstatement.setString(2, sno);
             i = pstatement.executeUpdate(); //执行修改操作，返回影响的行数
             if(i == 1){          //修改成功返回true
                 return true;
             }
         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
         return false;
     }

     //测试增删改查
     public static void main(String args[]){
         StudentDA stuDA = new StudentDA();
         dbConn = stuDA.dBConnection();
         //测试查询
         System.out.println("测试----查询所有记录 ");
         List<Student> stuList = stuDA.selectAllStudent();
         for(Student stu:stuList){
             System.out.println(stu.toString());
         }

 /*        //测试插入
         System.out.println("测试----插入一条记录 ");
         Student stu = new Student("200215334","test2","男","CS",25);
         if(stuDA.insertStudent(stu)){
             System.out.println("插入成功");
         }else{
             System.out.println("插入失败");
         }

         //测试根据sno删除记录
         if(stuDA.deleteStudent("200215334")){
             System.out.println("删除成功");
         }else{
             System.out.println("删除失败");
         }

         //测试更新
         if(stuDA.updateStudent("200215333", 33)){
             System.out.println("更新成功");
         }else{
             System.out.println("更新失败");
         }*/
     }
 }