Web前后端数据交互技术 课件 8.1.2jdbc更新数据库表的内容

——江西应用技术职业学院web前后端数据交互技术JDBC操作8.1.301JDBC更新数据JDBC操作实例JDBC连接数据库编写更新的sql语句执行sql语句关闭数据连接，释放资源案例步骤//定义驱动，帐号，密码，连接地址publicstaticfinalStringdriver="com.mysql.cj.jdbc.Driver";//驱动publicstaticfinalStringuser="root";

//帐号publicstaticfinalStringpassword="root";//密码publicstaticfinalStringurl="jdbc:mysql://localhost:3306/sw?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT";publicstaticConnectioncon=null;//加载驱动static{try{Class.forName(driver);}catch(ClassNotFoundExceptione){e.printStackTrace();}}//编写连接的方法publicstaticConnectiongetConnection(){try{con=DriverManager.getConnection(url,user,password);}catch(SQLExceptione){e.printStackTrace();}returncon;}publicstaticvoidmain(String[]args){//执行更新数据的sql语句

Scannerscanner=newScanner(System.in);System.out.println("请输入帐号");Stringusername=scanner.next();System.out.println("请输入密码");Stringpassword=scanner.next();scanner.close();//编写更新的sqlStringsql="updateusersetuser_name='超人'whereid='1'";//定义连接和执行Connectionconn=null;Statementsmt=null;try{//获取连接conn=getConnection();//获取执行smt=conn.createStatement();//执行更新的动作intres=smt.executeUpdate(sql);if(res>0){

System.out.println("更新成功");

}else{

System.out.println("更新失败");

}

smt.close();

conn.close();

}catch(SQLExceptione){

e.printStackTrace();

}02JDBC删除数据JDBC操作实例JDBC连接数据库编写删除的sql语句执行sql语句关闭数据连接，释放资源案例步骤//定义驱动，帐号，密码，连接地址publicstaticfinalStringdriver="com.mysql.cj.jdbc.Driver";//驱动publicstaticfinalStringuser="root";

//帐号publicstaticfinalStringpassword="root";//密码publicstaticfinalStringurl="jdbc:mysql://localhost:3306/sw?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT";publicstaticConnectioncon=null;//加载驱动static{try{Class.forName(driver);}catch(ClassNotFoundExceptione){e.printStackTrace();}}//编写连接的方法publicstaticConnectiongetConnection(){try{con=DriverManager.getConnection(url,user,password);}catch(SQLExceptione){e.printStackTrace();}returncon;}publicstaticvoidmain(String[]args){//执行删除数据的sql语句

Scannerscanner=newScanner(System.in);System.out.println("请输入帐号");Stringusername=scanner.next();System.out.println("请输入密码");Stringpassword=scanner.next();scanner.close();//编写一条sqlStringsql="deletefromuserwhereid='1'";

//定义连接，执行Connectionconn=null;Statementsmt=null;

try{

//获取连接和执行conn=getConnection();smt=conn.createStatement();

//执行删除

intres=smt.executeUpdate(sql);if(res>0){

System.out.println("删除成功");

}else{

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