添加
package tainjia;import java.sql.ResultSet;import java.sql.Statement;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;public class Add {/** * @param args * @throws ClassNotFoundException * @throws SQLException */public static void main(String[] args) throws ClassNotFoundException, SQLException {// TODO Auto-generated method stubString driver="com.microsoft.sqlserver.jdbc.SQLServerDriver";String url="jdbc:sqlserver://Localhost:1433;DatabaseName=S2226"; String usernaem="sa"; String pwd="444555";Class.forName(driver); Connection con=DriverManager.getConnection(url,usernaem,pwd);Statement sta=con.createStatement();String sql="insert into Student values('李四',2000)";String name="select * from Student";ResultSet res=sta.executeQuery(name);if(res!=null){while(res.next()){System.out.println(res.getInt("Sid"));}}int count=sta.executeUpdate(sql);if(count>0){System.out.println("添加数据成功");}sta.close();con.close();}} 删除
package delete;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.SQLException;public class delect {/** * @param args * @throws ClassNotFoundException * @throws SQLException */public static void main(String[] args) throws ClassNotFoundException, SQLException {// TODO Auto-generated method stubString driver="com.microsoft.sqlserver.jdbc.SQLServerDriver";String url="jdbc:sqlserver://Localhost:1433;DatabaseName=S2226";String username="sa";String pwd="444555";Connection con;Class.forName(driver);con=DriverManager.getConnection(url,username,pwd);String sql="delete from Student where Sid=4";PreparedStatement ps=con.prepareStatement(sql);int count=ps.executeUpdate();if(ps!=null){if(count>0){System.out.println("删除成功");}else{System.out.println("删除失败");}}/*if(count>0){System.out.println("删除成功");}else{System.out.println("删除失败");}*/}} 登录package denglu;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.util.Scanner;public class denglu {/** * @param args * @throws SQLException */public static void main(String[] args) throws SQLException {// TODO Auto-generated method stubConnection con=null;String driver="com.microsoft.sqlserver.jdbc.SQLServerDriver";try {Class.forName(driver);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}String url="jdbc:sqlserver://Localhost:1433;DatabaseName=S2226";String username="sa";String pwd="444555";try { con=DriverManager.getConnection(url,username,pwd);} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}Scanner input=new Scanner(System.in);System.out.println("请输入用户名");String name=input.nextLine();System.out.println("请输入密码");String pwd1=input.nextLine();String sql="select count(1) as num from Student where Sname=? and Scalary=?";PreparedStatement ps=con.prepareStatement(sql); ps.setString(1,name); ps.setString(2,pwd1);ResultSet res=ps.executeQuery();if(res!=null){while(res.next()){//注释快捷键 ctrl+shift+/int count=res.getInt("num");if(count>0){System.out.println("登陆成功");}else{System.out.println("登录失败");}}}}} baseDao
package bao;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.DriverManager;public class baseDAO {public static final String DIVER_STRING="com.microsoft.sqlserver.jdbc.SQLServerDriver";public static final String URL_STRING="jdbc:sqlserver://192.168.60.124:1433;DatabaseName=Subway";public static final String USERNAME_STRING="sa";public static final String PWD_STRING="6375196";private Connection con;private PreparedStatement ps;private ResultSet rs;public int executeUpdate(String sql,Object...objects)throws SQLException{ ps=con.prepareStatement(sql);for (int i = 0; i <objects.length; i++) {ps.setObject(i+1, 1);}int count=ps.executeUpdate();return count;}//读取操作public ResultSet executeQuery(String sql,Object...objs)throws SQLException{ps=con.prepareStatement(sql);for (int i = 0; i < objs.length; i++) {ps.setObject(i+1, objs[i]);}rs=ps.executeQuery();return rs;}static{try {Class.forName(DIVER_STRING);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}}public Connection getConnection()throws SQLException{if(con==null||con.isClosed()){con=DriverManager.getConnection(URL_STRING,USERNAME_STRING,PWD_STRING);}return con;}public void closeResources() {// TODO Auto-generated method stub}} Testpackage bao;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;public class Test {/** * @param args * @throws SQLException */public static void main(String[] args) throws SQLException {/*// TODO Auto-generated method stub String url="com.microsoft.sqlserver.jdbc.SQLServerDriver";String username="sa";String pwd="6375196"; Connection con=DriverManager.getConnection(url, username, pwd);String sql="select * from subwayinfo id=？";PreparedStatement ps=con.prepareStatement(sql);ps.setInt(1, 1);ResultSet rs=ps.executeQuery();if(rs.next()){String subwayname=rs.getString("subwayname");System.out.println(subwayname);}rs.close(); ps.close(); con.close();*/baseDAO dao=new baseDAO();String sql="select * from subwayinfo where id=?";Object [] objs={1};dao.getConnection();ResultSet rs=dao.executeQuery(sql, objs);if(rs.next()){System.out.println(rs.getString("subwayname"));}dao.closeResources();}}
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