oracle 的饭后练习：

--顾客表
create table customer(
?customerID number(4) primary key,--顾客编号
?customer_name varchar2(20),--顾客姓名
?customer_add varchar2(40),--顾客地址
?customer_bir date,--顾客生日
?customer_tele varchar2(20)--顾客电话
?);
--插入数据
insert into customer values(1,'陆丰燕','北京西戎线胡同211号','08-5月-79','8769888');
insert into customer values(2,'陈家驹','北京东戎线胡同300号','01-9月-76','8888888');
insert into customer values(3,'王莲良','北京西戎线胡同298号','09-5月-83','6523144');
insert into customer values(4,'元件是','北京西戎线胡同297号','08-4月-62','1234567');
insert into customer values(5,'色那边','北京西戎线胡同200号','08-5月-77','8989898');

--员工表
create table employees(
?empID number(4) primary key,--员工编号
?emp_name varchar2(20),--员工姓名
?hire_date date,--受雇日期
?mgrID number(4),--经理编号
?sal number(7,2),--工资
?comm_rate number(7,2)--佣金比例
?);
--插入数据
insert into employees values (1,'tom','05-8月-99',2,1520,0.04);
insert into employees values (2,'mike','11-2月-78',null,4520,null);
insert into employees values (3,'jack','02-11月-98',1,820,0.03);

--定单表
create table orders(
?orderID number(4) primary key,--定单编号
?order_date date,--定单日期
?customerID number(4) references customer(customerID),--顾客编号
?empID number(4) references employees(empID)--员工编号
?);
--插入数据
--10张订单
insert into orders values(1,'05-7月-05',1,1);
insert into orders values(2,'08-7月-05',2,2);
insert into orders values(3,'15-7月-05',3,3);
insert into orders values(4,'25-8月-05',4,3);
insert into orders values(5,'08-8月-05',5,2);
insert into orders values(6,'03-8月-05',2,1);
insert into orders values(7,'02-7月-05',2,1);
insert into orders values(8,'12-7月-05',1,2);
insert into orders values(9,'6-9月-05',3,3);
insert into orders values(10,'31-10月-05',5,3);

--供应商表
create table provider(
?providerID number(4) primary key,--供应商编号
?provider_name varchar2(20),--供应商名称
?provider_add varchar2(40),--供应商地址
?provider_tel varchar2(20),--供应商电话
?account varchar2(40),--供应商帐号
?email varchar2(40)--供应商电子邮件
?);
--插入数据
insert into provider values
?(11,'中兴','北京','010564578','95588123456789','mmm@123.com');
insert into provider values
?(12,'大华','上海','021564578','95599123456789','kkk@123.com');
insert into provider values
?(13,'何氏','广州','020564578','95500123456789','fff@123.com');
?
--商品类别表
create table categorys(
?categoryID number(4) primary key,--种类编号
?category_name varchar2(20),--种类名称
?category_desc varchar2(40)--种类描述
?);
--插入数据
insert into categorys values(1,'生鲜','鸡鸭鱼肉，冷冻食品');
insert into categorys values(2,'杂货','厨房用品等');
insert into categorys values(3,'食品','生鲜以外的食品');
insert into categorys values(4,'日用','服装，纺织类');

--商品表
create table products(
?productID number(4) primary key,--商品编号
?product_name varchar2(20),--商品名称
?income_price number(7,2),--进货单价
?providerID number(4) references provider(providerID),--供应商编号
?quantity number(4),--库存数量
?sales_price number(9,2),--出售单价
?categoryID number(4) references categorys(categoryID)--类别编号
?);
--插入数据
insert into products values(1 ,'大宝',80 ,11,10,100,1);
insert into products values(2 ,'冰箱',60 ,12,30,80,3);
insert into products values(3 ,'彩电',30 ,13,20,50,2);
insert into products values(4 ,'牙膏',100,12,100,120,3);
insert into products values(5 ,'洗衣机',20 ,11,20,1000,1);
insert into products values(6 ,'微波炉',90 ,13,10,500,2);
insert into products values(7 ,'手纸',1,12,100,10,3);
insert into products values(8 ,'一次性纸杯',2 ,12,200,20,2);
insert into products values(9 ,'电脑',500,11,5,200,2);
insert into products values(10,'拖鞋',200,11,2,100,3);
insert into products values(11,'明星照片',300,13,100,350,1);
insert into products values(12,'502胶水',100,11,100,150,1);
insert into products values(13,'84消毒液',100,12,300,150,2);
insert into products values(14,'扑克牌',50 ,13,100,100,1);
insert into products values(15,'音响',90 ,