怎样编写一个java程序能通过jdbc访问数据库实现对数据库的插入、删除、修改和查询？

Posted 2023-05-16

参考技术A 1.增加\\x0d\\x0aString s1="insert into tableNames (id,name,password) values(myseq.nextval,?,?);"\\x0d\\x0aClass.forName(driver);\\x0d\\x0aConnection conn = DriverManager.getConnection(url,dbUser,dbPwd);\\x0d\\x0aPreparedStatement prepStmt = conn.prepareStatement(s1);\\x0d\\x0aprepStmt.setString(1,name);\\x0d\\x0aprepStmt.setString(2,password);\\x0d\\x0aResultSet rs=stmt.executeUpdate();\\x0d\\x0a2、删除\\x0d\\x0aString s2="delete from tbNames where name=?";\\x0d\\x0aClass.forName(driver);\\x0d\\x0aConnection conn = DriverManager.getConnection(url,dbUser,dbPwd);\\x0d\\x0aPreparedStatement prepStmt = conn.prepareStatement(s2);\\x0d\\x0aprepStmt.setString(1,name);\\x0d\\x0aResultSet rs=stmt.executeUpdate();\\x0d\\x0a3、修改\\x0d\\x0aString s3=“update tbNames set name=? where id=?”;\\x0d\\x0aClass.forName(driver);\\x0d\\x0aConnection conn = DriverManager.getConnection(url,dbUser,dbPwd);\\x0d\\x0aPreparedStatement prepStmt = conn.prepareStatement(s3);\\x0d\\x0aprepStmt.setString(1,name);\\x0d\\x0aprepStmt.setString(2,id);\\x0d\\x0aResultSet rs=stmt.executeUpdate();\\x0d\\x0a4、查询\\x0d\\x0aString s4="select id,name,password from tbNames";\\x0d\\x0aClass.forName(driver);\\x0d\\x0aConnection conn = DriverManager.getConnection(url,dbUser,dbPwd);\\x0d\\x0aStatement stmt=conn.createStatement();\\x0d\\x0aResultSet rs = stmt.executeQuery(s4);\\x0d\\x0awhile(rs.next)\\x0d\\x0aint id=rs.getInt(1);\\x0d\\x0aString name = rs.getString(2);\\x0d\\x0aString pwd=rs.getString(3);\\x0d\\x0aSystem.out.println(id+name+pwd); \\x0d\\x0a\\x0d\\x0a以上四步必须都得关闭连接；！！！\\x0d\\x0ars.close();\\x0d\\x0astmt.close();\\x0d\\x0aconn.close();

编写一个java程序，通过jdbc访问数据库实现对数据库的插入，删除，修改和查询操作

java

参考技术A 我刚写了一个只有插入的，望采纳
import java.sql.*;
import java.util.*;
public class TestPre
public static void main(String[] args)
int i=0,deptno=0;//i只做while循环使用，deptno是表dept2中的一个属性，类型是int
String dname=null,loc=null;//dname和loc也是表dept2的属性，类型是String
Scanner s=new Scanner(System.in);
System.out.println("请输入3个参数");
while(i<3)
try
deptno=s.nextInt();
i++;
dname=s.next();
i++;
loc=s.next();
i++;
catch(InputMismatchException e)
System.out.println("输入的类型不符,退出");
System.exit(-1);


Connection conn=null;
PreparedStatement pstmt=null;
try
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost/mydata?"+ "user=root&password=root");
pstmt=conn.prepareStatement("insert into dept2 values(?,?,?)");
pstmt.setInt(1, deptno);
pstmt.setString(2, dname);
pstmt.setString(3, loc);
pstmt.executeUpdate();
System.out.println("插入完成");
catch (ClassNotFoundException e)
System.out.println("连接数据库不成功，程序退出");
System.exit(-1);
catch (SQLException e)
System.out.println("连接数据库不成功，程序退出");
System.exit(-1);

finally
try
if(pstmt!=null)
pstmt.close();
pstmt=null;

if(conn!=null)
conn.close();
conn=null;

catch(SQLException e)
e.printStackTrace();



参考技术B 增删改查。。是做程序最简单的东西。。。楼主还是自己动手啊。。。。 参考技术C 1.增加
String s1="insert into tableNames (id,name,password) values(myseq.nextval,?,?);"
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,dbUser,dbPwd);
PreparedStatement prepStmt = conn.prepareStatement(s1);
prepStmt.setString(1,name);
prepStmt.setString(2,password);
ResultSet rs=stmt.executeUpdate();
2、删除
String s2="delete from tbNames where name=?";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,dbUser,dbPwd);
PreparedStatement prepStmt = conn.prepareStatement(s2);
prepStmt.setString(1,name);
ResultSet rs=stmt.executeUpdate();
3、修改
String s3=“update tbNames set name=? where id=?”;
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,dbUser,dbPwd);
PreparedStatement prepStmt = conn.prepareStatement(s3);
prepStmt.setString(1,name);
prepStmt.setString(2,id);
ResultSet rs=stmt.executeUpdate();
4、查询
String s4="select id,name,password from tbNames";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,dbUser,dbPwd);
Statement stmt=conn.createStatement();
ResultSet rs = stmt.executeQuery(s4);
while(rs.next)
int id=rs.getInt(1);
String name = rs.getString(2);
String pwd=rs.getString(3);
System.out.println(id+name+pwd);

以上四步必须都得关闭连接；！！！
rs.close();
stmt.close();
conn.close(); 参考技术D 增删改查 这是最基本的。 劝楼主还是自己动手写写。