一、系统需求分析

需求分析首先要确定研究分析的对象，这里的需求分析对象有两方：买家和卖家。

对于买家，需求是能够进行线上点餐，具体可以细化为：能够在线上获得餐品信息和进行点餐行为。买家作为消费者，都想得到更为优质的服务体验，希望能够通过较为简单顺利的操作就可以吃到满足自己口味的菜肴。这就要求系统界面能够生动形象地有效呈现出点餐的各项信息，菜品的价格，可以选择就坐的餐桌的数目等情况以及加餐时简洁的操作界面。

对于卖家，需求是能够对菜品进行增查删改以及增加会员，具体可以细化为，能够线上获得全部的菜品信息，添加菜品，修改菜品价格，删除菜品，增加会员。卖家即为商家，商家要能够高效地获取这些的信息，当然是图形化界面和几何形式的信息呈现最为直接明了。

二、系统设计

1. 功能结构设计

2、概念设计

2.2.1 bill_food表E-R图

2.2.2 bills表E-R图

2.2.3 categories E-R图

2.2.4 discounts表 E-R图

2.2.5 emp表E-R图

2.2.6 food 表E-R图

2.2.7 member表E-R图

2.2.8 member_point_bill表E-R图

2.2.9 servers表E-R图

2.2.10 tables表E-R图

2.2.11 user表E-R图

3. 逻辑设计（表的设计）

①bill_food表

CREATE TABLE `bill_food` (
  `id_food` int NOT NULL,
  `id_bill` int NOT NULL,
  `num` int NOT NULL,
  PRIMARY KEY (`id_food`,`id_bill`),
  KEY `FK_bill_food2` (`id_bill`),
  CONSTRAINT `FK_bill_food` FOREIGN KEY (`id_food`) REFERENCES `food` (`id_food`) ON DELETE RESTRICT ON UPDATE RESTRICT,
  CONSTRAINT `FK_bill_food2` FOREIGN KEY (`id_bill`) REFERENCES `bills` (`id_bill`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ;

②bills表

CREATE TABLE `bills` (
  `id_bill` int NOT NULL,
  `id_table` int NOT NULL,
  `id_member` int DEFAULT NULL,
  `time_order` datetime NOT NULL,
  `time_pay` datetime DEFAULT NULL,
  `money` int NOT NULL,
  PRIMARY KEY (`id_bill`),
  KEY `FK_bill_member` (`id_member`),
  KEY `FK_table_bill` (`id_table`),
  KEY `time_order` (`time_order`),
  CONSTRAINT `FK_bill_member` FOREIGN KEY (`id_member`) REFERENCES `member` (`id_member`) ON DELETE RESTRICT ON UPDATE RESTRICT,
  CONSTRAINT `FK_table_bill` FOREIGN KEY (`id_table`) REFERENCES `tables` (`id_table`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ;

③categories表

CREATE TABLE `categories` (
  `category` char(20) NOT NULL,
  PRIMARY KEY (`category`)
);

④discounts表

CREATE TABLE `discounts` (
  `id_discount` int NOT NULL,
  `off_price` int NOT NULL,
  `require_points` int NOT NULL,
  PRIMARY KEY (`id_discount`)
) ;

⑤emp表

CREATE TABLE `emp` (
  `id_emp` int NOT NULL,
  `id_server` int DEFAULT NULL,
  `name_emp` char(20) NOT NULL,
  `sex_emp` char(1) DEFAULT NULL,
  `phone_num` char(11) DEFAULT NULL,
  `position` char(20) DEFAULT NULL,
  PRIMARY KEY (`id_emp`)
);

⑥food表

CREATE TABLE `food` (
  `id_food` int NOT NULL,
  `category` char(20) NOT NULL,
  `name_food` char(20) NOT NULL,
  `introduction` char(100) DEFAULT NULL,
  `price` int NOT NULL,
  `url` char(100) DEFAULT NULL,
  PRIMARY KEY (`id_food`),
  KEY `FK_food_category` (`category`),
  CONSTRAINT `FK_food_category` FOREIGN KEY (`category`) REFERENCES `categories` (`category`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ;

⑦member表

CREATE TABLE `member` (
  `id_member` int NOT NULL,
  `name_member` char(20) DEFAULT NULL,
  `points` int NOT NULL,
  `sex` char(1) DEFAULT NULL,
  `phone_num` char(11) DEFAULT NULL,
  PRIMARY KEY (`id_member`)
) ;

⑧member_point_bills表

CREATE TABLE `member_point_bill` (
  `id_point_bill` int NOT NULL,
  `id_member` int NOT NULL,
  `time_point` datetime NOT NULL,
  `point` int NOT NULL,
  `note` char(20) DEFAULT NULL,
  PRIMARY KEY (`id_point_bill`),
  KEY `FK_member_point_bill` (`id_member`),
  CONSTRAINT `FK_member_point_bill` FOREIGN KEY (`id_member`) REFERENCES `member` (`id_member`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ;

⑨servers表

CREATE TABLE `servers` (
  `id_server` int NOT NULL,
  `id_emp` int NOT NULL,
  PRIMARY KEY (`id_server`),
  KEY `FK_to_server` (`id_emp`),
  CONSTRAINT `FK_to_server` FOREIGN KEY (`id_emp`) REFERENCES `emp` (`id_emp`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ;

⑩tables表

CREATE TABLE `tables` (
  `id_table` int NOT NULL,
  `id_server` int NOT NULL,
  `num_people` int NOT NULL,
  `id_bill` int DEFAULT NULL,
  `id_member` int DEFAULT NULL,
  PRIMARY KEY (`id_table`),
  KEY `FK_server_table` (`id_server`),
  CONSTRAINT `FK_server_table` FOREIGN KEY (`id_server`) REFERENCES `servers` (`id_server`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ;

11.user表

CREATE TABLE `user` (
  `user_id` varchar(4) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `user_password` varchar(255) NOT NULL,
  `user_name` varchar(255) DEFAULT NULL,
  `user_position` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`user_id`)
);

源码获取

源码获取和python实现在下一篇文章中。
基于python+MySQL的餐厅点餐系统（python代码实现）