打扰了 请帮我一下 为什么信息没有添加到数据库中

Question

不成功应该有错误信息
String updateSql="update info set class1="+class1+", class2="+class2+", title="+title+", shuom="+shuom+", tel="+"tel"+", email="+email+", image="+image+", content="+content+", addDate="+addDate+" where id="+id;这句不对吧,  应该是'', 如"'"+fieldvalue+"'"                                    

Answer 1

我现在搞asp 业余时间学jsp java 面向对象的 所以就向用
  
// 向数据增加信息
   public void executeAddInfo(Info newInfo){
 int class1=newInfo.getClass1();
 int class2=newInfo.getClass2();
 String title=newInfo.getTitle();
 String shuom=newInfo.getExplain();
 String tel=newInfo.getTel();
 String email=newInfo.getEmail();
 String contact=newInfo.getContact();
 String image=newInfo.getImage();
 String content=newInfo.getContent();
 Date addDate=new Date();
 /*
  * add info to database
  */
 String addSql="insert into info values("+title+","+class1+","+class2+","+image+","+addDate+","+content+","+contact+","+tel+","+email+",false)";
 try {
stm.executeUpdate(addSql);
} catch (SQLException e) {
e.printStackTrace();
System.err.print("添加信息出错");
}
   }
来实现 添加信息 不知道这样的面向对象的思路对不对
我又想是不是把该方法放到 Info类里 更合适一些
请高手指点

Answer 2

insert into info values("+title+","+class1+","+class2+","+image+","+addDate+","+content+","+contact+","+tel+","+email+",false)";在values前面加入每个属性对应的项
insert into info（title，class1，class2，image，addDate，content，contact，tel，email，false ） values("+title+","+class1+","+class2+","+image+","+addDate+","+content+","+contact+","+tel+","+email+",false)";

Answer 3

改为String updateSql="update info set class1='"+class1+"', class2='"+class2+"', title='"+title+"', shuom='"+shuom+"', tel='"+tel"+"', email='"+email+"', image='"+image+"'', content='"+content+"', addDate='"+addDate+"' where id="+id;