摘要： 语法结构如下：alter table tablename add (column datatype [default value][null/not null],….);alter table tablename modify (column datatype [default value][null/not null],….);alter table tablename drop (column);例子：增加列alter table t_jm_user add USR_EmailValidate CHAR(1) default 'N' not null;修改列alter ta 阅读全文

摘要： java 获取本机ippublic class Test3 { public static void main(String[] args) throws UnknownHostException { InetAddress inet = InetAddress.getLocalHost(); System.out.println("本机的ip=" + inet.getHostAddress()); }} 阅读全文