经典电商数据库分析构建（一）

传统电商表的分析以及设计（简单版，只包括商家和用户关系处理）

站在用户角度

首先有一张用户表，包括用户的基本信息。
然后有一张商品表，包括商品的基本信息；除此之外，应该还有商家的id作为外键，可以帮助用户了解商品的所属。
然后订单表，一个订单可以有多个商品，每个商品应该有用户购买的数量和单价以及总价。一个订单应该还包括该订单的总价，订单编号等。所以，一条数据不可能表示这些信息。
所以要有一个中间表，我们称之为订单项表，表示订单中每个商品的信息。
订单项中包括 id、商品id、购买数量、单项总价、订单id、用户id。
订单中包括：id、订单日期、订单状态、总价。

站在商家的角度

首先商家表，包括基本信息。
对于产品，只要包括基本信息即可。同样。需要加上商家id，表示所属。
对于订单，商家应该可以查询到每件商品的卖出数量及总价，上述设计以及可以满足。
同样，商家还需要统计订单。查看哪位用户购买的商品，购买数量。上述设计也可以满足。

设计表

customer(用户表): cid、cname、cphone、caddress
merchant(商家表):mid、mname、mphone、maddress
product(商品表):pid、pname、pprice、premain、mid
order(订单表)：oid、odatetime、ostate、osummoney、cid
orderitem(订单项表)：oiid、iobuynum、iosummoney、pid、oid

建表

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for `customer`
-- ----------------------------
DROP TABLE IF EXISTS `customer`;
CREATE TABLE `customer` (
  `cid` int(11) NOT NULL auto_increment,
  `cname` varchar(20) default NULL,
  `cphone` varchar(11) default NULL,
  `caddress` varchar(200) default NULL,
  PRIMARY KEY  (`cid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


-- ----------------------------
-- Table structure for `merchant`
-- ----------------------------
DROP TABLE IF EXISTS `merchant`;
CREATE TABLE `merchant` (
  `mid` int(11) NOT NULL auto_increment,
  `mname` varchar(20) default NULL,
  `mphone` varchar(11) default NULL,
  `maddress` varchar(200) default NULL,
  PRIMARY KEY  (`mid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


-- ----------------------------
-- Table structure for `orders`
-- ----------------------------
DROP TABLE IF EXISTS `orders`;
CREATE TABLE `orders` (
  `oid` int(11) NOT NULL auto_increment,
  `odatetime` datetime default NULL,
  `ostate` varchar(20) default NULL,
  `osummoney` double default NULL,
  `cid` int(11) NOT NULL,
  PRIMARY KEY  (`oid`),
  KEY `cid` (`cid`),
  CONSTRAINT `order_ibfk_1` FOREIGN KEY (`cid`) REFERENCES `customer` (`cid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


-- ----------------------------
-- Table structure for `ordersitem`
-- ----------------------------
DROP TABLE IF EXISTS `ordersitem`;
CREATE TABLE `ordersitem` (
  `oiid` int(11) NOT NULL auto_increment,
  `iobuynum` int(11) default NULL,
  `iosummoney` double default NULL,
  `pid` int(11) NOT NULL,
  `oid` int(11) NOT NULL,
  PRIMARY KEY  (`oiid`),
  KEY `pid` (`pid`),
  KEY `oid` (`oid`),
  CONSTRAINT `ordersitem_ibfk_2` FOREIGN KEY (`oid`) REFERENCES `orders` (`oid`),
  CONSTRAINT `ordersitem_ibfk_1` FOREIGN KEY (`pid`) REFERENCES `product` (`pid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;



-- ----------------------------
-- Table structure for `product`
-- ----------------------------
DROP TABLE IF EXISTS `product`;
CREATE TABLE `product` (
  `pid` int(11) NOT NULL auto_increment,
  `pname` varchar(20) default NULL,
  `pprice` double default NULL,
  `premain` int(11) default NULL,
  `mid` int(11) NOT NULL,
  PRIMARY KEY  (`pid`),
  KEY `mid` (`mid`),
  CONSTRAINT `product_ibfk_1` FOREIGN KEY (`mid`) REFERENCES `merchant` (`mid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

插入语句

顾客

insert into customer values(null,'张三','15639854081','南阳');
insert into customer values(null,'李四','17439804082','上海');
insert into customer values(null,'王五','13438454088','长春');
insert into customer values(null,'赵六','18239454061','上海');
insert into customer values(null,'刘八','15439854382','北京');
insert into customer values(null,'旺财','17433854087','广东');

商家

insert into merchant values(null,'广州宝洁','800-400-300','广州'),(null,'北京老板','808-300-446','北京'),(null,'郑州宇通','888-400-533','郑州');

产品

insert into product values(null,'佳洁士炫白牙齿牙膏',6.8,300,1),(null,'舒肤佳',4.5,400,1),(null,'飘柔',20.8,5,1),(null,'海飞丝',32.5,20,1);
insert into product values(null,'老板油烟机',566.00,40,2),(null,'老板插座',56.00,400,2),(null,'老板风扇',128.00,360,2),(null,'老板压力锅',288.00,460,2);
insert into product values(null,'宇通油电混合客车',200000,10,3),(null,'宇通电动客车',120000,20,3),(null,'宇通重卡',400000,60,3);

订单

insert into orders values(1,'2016-03-02 12:30:02','未支付',0,1);
insert into orders values(2,'2016-02-02 09:30:02','已支付',0,3);
insert into orders values(3,'2016-01-02 12:28:02','已支付',0,5);
insert into orders values(4,'2016-01-02 12:28:02','已支付',0,4);

订单项

--订单1：有三件商品
insert into ordersitem values(null,3,20.40,1,1),(null,2,41.6,3,1),(null,1,400000,11,1);
--订单2：有两件商品
insert into ordersitem values(null,1,566,5,2),(null,1,128,7,2);
--订单3：有一件商品
insert into ordersitem values(null,1,120000,10,3);
--订单4：有三件商品
insert into ordersitem values(null,3,20.40,1,4),(null,1,6.8,1,4),(null,1,400000,11,4);

任务

从商品表中查询以“老板”两个字开头的商品名称及数量，并按数量降序排序（用户搜索）
查询所有的商品名、价格、所属厂家、产地）（商品信息展示）
从订单表中查询购买订单编号为“2”的所有商品的商品名字、单价、数量、顾客名字及订单日期（用户查看订单）
更新订单1：更新状态为“已支付”，总价格为实际价格。显示：订单编号为“1”的所有商品的商品名字、单价、数量、顾客名字及订单日期，总价格，订单状态（用户支付查看订单）
删除订单3信息（用户取消订单）
查询编号为2的商品的售出数量、名字、购买人名字（商家查看某件商品出售情况）
查看宝洁公司的销售情况,按照销售数量由高到低排序（商家查看售出数据）
将售出的商品按照售出数量由高到低排序（管理员查看售出数据）

答案

1. SELECT 
  pname 商品名,
  premain 剩余量 
FROM
  product 
WHERE pname LIKE '老板%' 
ORDER BY premain ;
2. SELECT 
  pname 商品名,
  premain 剩余量,
  pprice 价格,
  mname 所属厂家,
  maddress 产地 
FROM
  product,
  merchant 
WHERE product.mid = merchant.mid ;

3.SELECT 
  pname 商品名,
  premain 剩余量,
  pprice 价格,
  cname 顾客名,
  odatetime 订单日期 
FROM
  product,
  customer,
  orders,
  ordersitem 
WHERE ordersitem.pid = product.pid 
  AND ordersitem.oid = orders.oid 
  AND orders.cid = customer.cid 
  AND orders.oid = 2 ;

4.UPDATE 
  orders 
SET
  orders.ostate = '已支付',
  orders.osummoney = 
  (SELECT 
    (SELECT 
      SUM(
        ordersitem.iobuynum * ordersitem.iosummoney
      ) 
    FROM
      ordersitem 
    WHERE ordersitem.oid = orders.oid 
      AND ordersitem.oid = 1 
    GROUP BY ordersitem.oid)) 
WHERE orders.oid = 1 ;

参考：http :/ / huangyunbin.iteye.com / blog / 1190882 


5.原子操作
DELETE FROM ordersitem WHERE oid=3;
DELETE FROM orders WHERE oid=3;

6.   SELECT 
  SUM(ordersitem.iobuynum) 售出数量,
SUM(ordersitem.iobuynum*product.pprice) 总价,
  product.pname 商品名称,
  customer.cname 顾客名字
FROM
  product,
  customer,
  orders,
  ordersitem 
WHERE ordersitem.pid = product.pid 
  AND ordersitem.oid = orders.oid 
  AND orders.cid = customer.cid 
  AND product.pid = 1 GROUP BY customer.cid;

7.  SELECT 
  SUM(ordersitem.iobuynum) 售出数量,
  SUM(
    ordersitem.iobuynum * product.pprice
  ) 总价,
  product.pname 商品名字 
FROM
  product,
  ordersitem,
  merchant 
WHERE ordersitem.pid = product.pid 
  AND product.mid = merchant.mid 
  AND merchant.mname = "广州宝洁" 
GROUP BY product.pname ;

8. SELECT 
  SUM(ordersitem.iobuynum) 售出数量,
  SUM(
    ordersitem.iobuynum * product.pprice
  ) 总价,
  product.pname 商品名字 
FROM
  product,
  ordersitem,
  merchant 
WHERE ordersitem.pid = product.pid 
  AND product.mid = merchant.mid 

GROUP BY product.pname ORDER BY ordersitem.`iobuynum` DESC;

附：所有操作源码

/*
Navicat MySQL Data Transfer

Source Server         : 123
Source Server Version : 50027
Source Host           : localhost:3306
Source Database       : mygist

Target Server Type    : MYSQL
Target Server Version : 50027
File Encoding         : 65001

Date: 2016-03-16 20:00:31
*/

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for `customer`
-- ----------------------------
DROP TABLE IF EXISTS `customer`;
CREATE TABLE `customer` (
  `cid` int(11) NOT NULL auto_increment,
  `cname` varchar(20) default NULL,
  `cphone` varchar(11) default NULL,
  `caddress` varchar(200) default NULL,
  PRIMARY KEY  (`cid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of customer
-- ----------------------------
INSERT INTO `customer` VALUES ('1', '张三', '15639854081', '南阳');
INSERT INTO `customer` VALUES ('2', '李四', '17439804082', '上海');
INSERT INTO `customer` VALUES ('3', '王五', '13438454088', '长春');
INSERT INTO `customer` VALUES ('4', '赵六', '18239454061', '上海');
INSERT INTO `customer` VALUES ('5', '刘八', '15439854382', '北京');
INSERT INTO `customer` VALUES ('6', '旺财', '17433854087', '广东');

-- ----------------------------
-- Table structure for `merchant`
-- ----------------------------
DROP TABLE IF EXISTS `merchant`;
CREATE TABLE `merchant` (
  `mid` int(11) NOT NULL auto_increment,
  `mname` varchar(20) default NULL,
  `mphone` varchar(11) default NULL,
  `maddress` varchar(200) default NULL,
  PRIMARY KEY  (`mid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of merchant
-- ----------------------------
INSERT INTO `merchant` VALUES ('1', '广州宝洁', '800-400-300', '广州');
INSERT INTO `merchant` VALUES ('2', '北京老板', '808-300-446', '北京');
INSERT INTO `merchant` VALUES ('3', '郑州宇通', '888-400-533', '郑州');

-- ----------------------------
-- Table structure for `orders`
-- ----------------------------
DROP TABLE IF EXISTS `orders`;
CREATE TABLE `orders` (
  `oid` int(11) NOT NULL auto_increment,
  `odatetime` datetime default NULL,
  `ostate` varchar(20) default NULL,
  `osummoney` double default NULL,
  `cid` int(11) NOT NULL,
  PRIMARY KEY  (`oid`),
  KEY `cid` (`cid`),
  CONSTRAINT `order_ibfk_1` FOREIGN KEY (`cid`) REFERENCES `customer` (`cid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of orders
-- ----------------------------
INSERT INTO `orders` VALUES ('1', '2016-03-02 12:30:02', '已支付', '400144.4', '1');
INSERT INTO `orders` VALUES ('2', '2016-02-02 09:30:02', '已支付', '694', '3');
INSERT INTO `orders` VALUES ('4', '2016-01-02 12:28:02', '已支付', '0', '4');

-- ----------------------------
-- Table structure for `ordersitem`
-- ----------------------------
DROP TABLE IF EXISTS `ordersitem`;
CREATE TABLE `ordersitem` (
  `oiid` int(11) NOT NULL auto_increment,
  `iobuynum` int(11) default NULL,
  `iosummoney` double default NULL,
  `pid` int(11) NOT NULL,
  `oid` int(11) NOT NULL,
  PRIMARY KEY  (`oiid`),
  KEY `pid` (`pid`),
  KEY `oid` (`oid`),
  CONSTRAINT `ordersitem_ibfk_1` FOREIGN KEY (`pid`) REFERENCES `product` (`pid`),
  CONSTRAINT `ordersitem_ibfk_2` FOREIGN KEY (`oid`) REFERENCES `orders` (`oid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of ordersitem
-- ----------------------------
INSERT INTO `ordersitem` VALUES ('1', '3', '20.4', '1', '1');
INSERT INTO `ordersitem` VALUES ('2', '2', '41.6', '3', '1');
INSERT INTO `ordersitem` VALUES ('3', '1', '400000', '11', '1');
INSERT INTO `ordersitem` VALUES ('4', '1', '566', '5', '2');
INSERT INTO `ordersitem` VALUES ('5', '1', '128', '7', '2');
INSERT INTO `ordersitem` VALUES ('7', '3', '20.4', '1', '4');
INSERT INTO `ordersitem` VALUES ('8', '1', '6.8', '1', '4');
INSERT INTO `ordersitem` VALUES ('9', '1', '400000', '11', '4');

-- ----------------------------
-- Table structure for `product`
-- ----------------------------
DROP TABLE IF EXISTS `product`;
CREATE TABLE `product` (
  `pid` int(11) NOT NULL auto_increment,
  `pname` varchar(20) default NULL,
  `pprice` double default NULL,
  `premain` int(11) default NULL,
  `mid` int(11) NOT NULL,
  PRIMARY KEY  (`pid`),
  KEY `mid` (`mid`),
  CONSTRAINT `product_ibfk_1` FOREIGN KEY (`mid`) REFERENCES `merchant` (`mid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of product
-- ----------------------------
INSERT INTO `product` VALUES ('1', '佳洁士炫白牙齿牙膏', '6.8', '300', '1');
INSERT INTO `product` VALUES ('2', '舒肤佳', '4.5', '400', '1');
INSERT INTO `product` VALUES ('3', '飘柔', '20.8', '5', '1');
INSERT INTO `product` VALUES ('4', '海飞丝', '32.5', '20', '1');
INSERT INTO `product` VALUES ('5', '老板油烟机', '566', '40', '2');
INSERT INTO `product` VALUES ('6', '老板插座', '56', '400', '2');
INSERT INTO `product` VALUES ('7', '老板风扇', '128', '360', '2');
INSERT INTO `product` VALUES ('8', '老板压力锅', '288', '460', '2');
INSERT INTO `product` VALUES ('9', '宇通油电混合客车', '200000', '10', '3');
INSERT INTO `product` VALUES ('10', '宇通电动客车', '120000', '20', '3');
INSERT INTO `product` VALUES ('11', '宇通重卡', '400000', '60', '3');

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原文地址：https://www.cnblogs.com/wanghuaijun/p/6890721.html