章猛.txt

关于oracle和sql的书籍和ppt教程,非常好,本人珍藏品

create table variety (vid number,vname varchar2(20));
alter table variety add constraint pk_variety_id primary key(vid);



create table goodsz (gid number,gname varchar2(20),vid number);
alter table goodsz add constraint pk_goods_gid primary key (gid);
alter table goodsz add constraint fk_goods_vid_variety_vid foreign key(vid) references      variety(vid) on delete set null;
alter table goodsz add (price number);
alter table goodsz modify (price number not null);
alter table goodsz drop (price);
alter table goodsz add (area varchar2(20));
alter table goodsz add constraint ck_goodsz_area check (area in ('内地','香港','台湾'));