MySQL之petstore
话不多说，一切都在mysql代码中，直接在这里插入代码片上代码：
创建petstore 数据库与表-
-----1--------
create database petstore;
----------2---------
use petstore;
create table account (
userid char(6) not null,
fullname varchar(10) not null,
password varchar(20) not null,
sex char(2) not null,
address varchar(40) null,
email varchar(20) null,
phone varchar(11) not null,
primary key (userid)
);
create table category(
catid char(10) not null,
catname varchar(20) null,
primary key (catid)
);
create table product(
productid char(10) not null,
catid char(10) not null,
name varchar(30) null,
descn text null,
listprice decimal(10,2) null,
unitcost decimal(10,2) null,
qty int(11) not null,
primary key (productid)
);
create table orders (
orderid int(11) not null auto_increment,
userid char(6) not null,
orderdate datetime not null,
totalprice decimal(10,2) default null,
status tinyint(1) default null,
primary key (orderid)
);
create table lineitem (
orderid int(11) not null,
itemid char(10) not null,
quantity int(11) not null,
unitprice decimal(10,2) not null,
primary key (orderid,itemid)
);
建立数据完整性约束—
-------3------
alter table product
add foreign key (catid)
references category(catid)
on delete restrict;
alter table orders
add foreign key (userid)
references account(userid)
on delete restrict
on update restrict;
alter table lineitem
add foreign key (itemid)
references product(productid)
on delete cascade
on update cascade;
alter table lineitem
add foreign key (orderid)
references orders(orderid)
on delete cascade;
alter table account
add check(sex in ('男','女'));
数据插入-1-用户表-
--------4---------
insert into account
values('u0001','刘晓和','123456','男','广东深圳市','[email protected]','17885091066');
insert into account
values('u0002','张嘉庆','147369','男','广东深圳市','[email protected]','17885061235');
insert into account
values('u0003','李天威','131452','男','贵州毕节市','[email protected]','17885091065');
insert into account
values('u0004','陈浪','584145','女','广东珠海市','[email protected]','16658461684');
insert into account
values('u0005','吴晶','852416','女','广东广州市','[email protected]','15599851352');
数据插入–2–商品分类表-
--------4---------
insert into category values('01','鸟类',' ');
insert into category values('02','猫',' ');
insert into category values('03','狗',' ');
insert into category values('04','鱼',' ');
insert into category values('05','爬行类',' ');
ERROR 1136 (21S01): Column count doesn’t match value count at row 1
出现这种报错是字段名与值不匹配，少写了值。
可能 出现的情况为：
1.插入字段的时候字段名或者值少写了；
2.进行蠕虫复制的时候，想把部分字段名复制到另一张表当中，字段名或者值少写了。
把缺少的值添加上问题就解决了！
在Mysql8.0版本中可以插入空值，在后面写一个null就可以，在5.5版本中，不能插入空值
–正确–
insert into category values('01','鸟类');
insert into category values('02','猫');
insert into category values('03','狗');
insert into category values('04','鱼');
insert into category values('05','爬行类');
数据插入—3—商品表-
--------4---------
insert into product
values('AV-CB-01','05','亚马逊鹦鹉','75岁以上高龄的好伙伴',50.00,60.00,100);
insert into product
values('AV-SB-02','05','燕雀','非常好的减压宠物',45.00,50.00,98);
insert into product
values('FI-FW-01','05','景丽','来自日本的淡水鱼',38.00,45.50,300);
insert into product
values('FI-FW-02','01','金鱼','来自中国的淡水鱼',6.80,6.60,100);
insert into product
values('FI-SW-01','01','天使鱼','来自澳大利亚的海水鱼',10.00,21.05,100);
insert into product
values('FI-SW-02','01','海鲨','来自澳大利亚的海水鱼',20.05,32.00,200);
–注意：可再加：–
数据插入----4----订单表-
--------4---------
insert into orders values(20191010,'u0001','2022-01-20 20:10:08',52.00,0);
insert into orders values(20191011,'u0002','2022-01-21 10:30:20',66.50,0);
insert into orders values(20191012,'u0003','2022-01-22 12:20:06',88.88,0);
insert into orders values(20191013,'u0004','2022-01-23 16:16:20',99.00,1);
insert into orders values(20191014,'u0005','2022-01-26 20:20:20',100.00,0);
数据修改与删除-1-数据修改-
-----5-------
update product
set unitcost=(qty*unitcost+50*15)/(qty+50)
where name='天使鱼';
update product
set listprice=unitcost*1.2,qty=qty+50
where name='天使鱼';
–合并–
update product
set unitcost=(qty*unitcost+50*15)/(qty+50)
listprice = unitcost*1.2,qty=qty+50
where name='天使鱼';
–2–修改订单的状态–
update orders
set status=1
where orderid='20191011';
–修改商品表的库存-*-
update lineitem,product
set product.qty=product.qty-lineitem.quantity
where lineitem.itemid=product.productid
and lineitem.orderid='20191011';
–合并–
update orders,lineitem.product
set orders.status=1,
product.qty=product.qty-lineitem.quantity
where orders.orderid=lineitem.orderid
and lineitem.itemid=product.productid
and orders.orderid='20191011';
ERROR 1049 (42000): Unknown database ‘lineitem’
--暂未解决--
–删除其所有订购信息，包括订单表和订单明细表的信息，涉及多表删除–
-*-delete orders,lineitem
from orders,lineitem
where orders.orderid=lineitem.id
and orders.userid='u0004';-*-
—删除用户表中的用户记录—
-*-delete from account where userid='u0004';-*-
-----一次删除所有数据------
-*-delete account,orders,lineitem
from account,orders,lineitem
where account.userid=orders.userid
and orders.orderid=lineitem.orderid
and account.userid='u0004';-*-
数据查询
------6------------：
-----列查询----
select fullname as 姓名,address as 地址,phone as 电话 from account;
select distinct itemid,unitprice from lineitem;
select orderid,itemid,quantity*unitprice as 金额 from lineitem;
select fullname,
case when sex='男' then '1'
when sex='女' then '0'
end as sex
from account;
（暂未）：
select name,
case
when unitcost < 500 then '抵挡商品'
when unitcost >=500 and unitcost<1000 then '中档商品'
else ‘高档商品'
end as 档次
from product;
-----条件查询----
select userid,totalprice,status from orders where totalprice >=50;
select * from orders
where orderdate >='2022-01-01' and orderdate <= '2022-02-20';
select fullname as 姓名,address as 地址,phone as 电话
from account where sex='女';
select * from account where fullname like '吴%';
select * from orders where totalprice>=52 and totalprice<=99;
select * from product where productid like '%F____';
-----多表查询--------
select orderid,name,quantity from lineitem
join product on(itemid=productid);
select fullname,totalprice from orders
join account on (orders.userid=account.userid)
where totalprice>=88;
select * from orders join account
on (orders.userid=account.userid)
where fullname='李天威';
select fullname,totalprice from orders
join account on (orders.userid=account.userid)
where orderdate<='2022-02-02' and sex='女';
select orderid,userid,orderdate from orders
where orderid in
(select orderid from lineitem where itemid='FI-FW-02');
select * from product where unitcost >=any
(select unitcost from product where name='景丽');
-----分类汇总与排序------
1)统计客户总数：
select count(*) as 总人数 from account;
2)计算orders表中每单的平均价：
select avg(totalprice) as 每单平均价 from orders;
3)计算orders表中的成交总额：
select sum(totalprice) as 成交总额 from orders;
4)显示orders表中的单笔最高成交额和最低成交额。
select max(totalprice) as 最高成交额,
min(totalprice) as 最低成交额
from orders;
5)按性别统计客户人数：
select sex,count(*) from account group by sex;
6）按商品类别统计各类商品总数、平均单价：
select catid,sum(qty),avg(unitcost) from product group by catid;
7)将客户信息按电话号码从大到小排序。
select * from account order by phone desc;
8)将orders表按用户号从小到大排序，用户号相同的按订单日期从大到小排序：
select * from orders order by userid,orderdate desc;
9)显示lineitem表中商品的购买总数量超过2件的商品号和购买总数量，并按购买数量从小大大排序：(暂未）：
select itemid,sum( quantity ) from lineitem
group by itemid
having sum ( quantity ) >=2
order by sum( quantity );
-----------7--------
-字段名用中文表示-
create view account_v1
as
(select userid as 用户号,fullname as 姓名,
password as 密码,sex as 性别,phone as 电话
from account where sex='男')
with check option;
select * from account_v1;
–查询客户信息–
select * from account_v1 where 姓名 like '李%';
—创建视图—
create view orders_v2
as
(select orderid,fullname,address,orderdate,totalprice
from orders join account
on (orders.userid=account.userid) );
select * from orders_v2;
----查询订单----
select * from orders_v2 where year(orderdate)=2022;
-----创建并查询视图------
create view lineitem_v3
as
(select name,orderdate,quantity,unitprice
from lineitem
join orders on (lineitem.orderid=orders.orderid)
join product on (lineitem.itemid=product.productid) );
—多余—
select * from lineitem_v3;
insert into account_v1
values('u0007','陈薇','131452','男','15984247598');
update orders_v2 set totalprice=totalprice+200
where orderid=20191012;
删除视图-1
delete from account_v1 where 用户号='u0009';
drop view order_v2,linitem_v3;
--------7----------
-1-
create index I_em_ind on account(email desc);
create index C_fa_ind on account(fullname,address);
create unique index U_na_ind on product(name(4));
–2–
alter table category
add primary key(catid),
add unique U_ca_ind(catname);
ERROR 1068 (42000): Multiple primary key defined
错误原因：定义了两次主键；
解决办法：去掉主键：primary key;
alter table lineitem
add primary key(orderid,itemid),
add index C_qu_ind(quantity,unitprice);
*–上同--
alter table account
add primary key(userid),
add unique U_fu_ind(fullname);
–*–同上–
—3—
create table shopcat(
shopcatid int(11) not null primary key,
userid char(10) not null,
itemid char(10) not null,
quantity int(11) not null,
unitprice decimal(10,2) not null,
index C_up_ind( userid,itemid )
);
show index from shopcat;
–*–
drop index C_up_ind on shopcat;
---
alter table orders partition by Key() partitions 3;
ERROR 1506 (HY000): Foreign keys are not yet supported in conjunction with partitioning
错误 1506年：尚未支持将外键与分区 SQL 语句： 更改表 。按哈希（id）分区
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