段湘南.txt

来自「关于oracle和sql的书籍和ppt教程,非常好,本人珍藏品」· 文本 代码 · 共 47 行

1，创建一个商品表 和 种类表；要求用到五个约束

create table commodity_1(cid number(4),cname varchar2(10),price number(7,2),kid number(4));

alter table commodity_1
add constraint pri_com_cid primary key(cid);

alter table commodity_1
add constraint check_price_1 check(price > 0);

alter table commodity_1
modify cname not null;

alter table commodity_1
add constraint uni_cname unique(cname);

create table class_1(classno number(4),classname varchar2(10));

alter table class_1
add constraint pri_cla_1 primary key(classno);

alter table commodity_1
add constraint fk_com_cid_cla_cno foreign key(cid) references class_1(classno);

alter table class_1
modify classname not null;

2，对刚才创建的商品表的列进行增，删，改操作，三个操作每个操作都有

alter table commodity_1
add  produce_area varchar2(10);

alter table commodity_1
add out_date date;

alter table commodity_1
drop(out_date);

alter table commodity_1
set unused(produce_area); 

alter table commodity_1
modify(cname varchar2(20));

alter table commodity_1
rename column kid to cla_id;