摘要:
oracle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 tablename add USR_EmailValidate CHAR(1) default 'N' not null;修改列al 阅读全文