jsp+mysql：Unknown column 'a' in 'field list'

开始还以为在servlet中操作数据库是使用mysql的下面的命令行，结果呵呵！！！要多看书！

String sql = "insert into food values("+id+","+date+","+babyclass+","+m1+","+m2+","+m3+","+m4+","+m5+");";

后来找到这么一段话：数据库的字符串要用引号区分的。   加单引号加的眼花，记录下来备用！

String sql = "insert into food(id,date,class,m1,m2,m3,m4,m5) values("+id+","+date+",'"+babyclass+"','"+m1+"','"+m2+"','"+m3+"','"+m4+"','"+m5+"')";

参考：数据库的字符串要用引号区分的