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+~~~mysql
+-- 1、创建数据库test01_market
+CREATE DATABASE test01_market;
+-- 2、创建表格customers
+CREATE TABLE customers(
+c_num INT(11),
+c_name VARCHAR(50),
+c_contact VARCHAR(50),
+c_city VARCHAR(50),
+c_birth date
+);
+-- | 字段名    | 数据类型    |
+-- | --------- | ----------- |
+-- | c_num     | int（11）   |
+-- | c_name    | varchar(50) |
+-- | c_contact | varchar(50) |
+-- | c_city    | varchar(50) |
+-- | c_birth   | date        |
+--
+-- **要求3：**将c_contact字段移动到c_birth字段后面
+ALTER TABLE customers MODIFY c_contact VARCHAR(50) AFTER c_birth;
+-- **要求4：**将c_name字段数据类型改为 varchar(70)
+ALTER TABLE customers MODIFY c_name VARCHAR(70);
+-- **要求5：**将c_contact字段改名为c_phone
+ALTER TABLE customers CHANGE c_contact c_phone VARCHAR(50);
+-- **要求6：**增加c_gender字段到c_name后面，数据类型为char(1)
+ALTER TABLE customers ADD c_gender CHAR(1) AFTER c_name;
+-- **要求7：**将表名改为customers_info
+RENAME TABLE customers TO customers_into;
+-- **要求8：**删除字段c_city
+ALTER TABLE customers_into DROP c_city;
+-- ```mysql
+-- 
+-- ```
+-- 
+-- ## 第2题
+-- 
+-- 1、创建数据库test02_library
+CREATE DATABASE test02_library;
+-- 2、创建表格books
+CREATE TABLE books(
+b_id int(11) NOT NULL UNIQUE COMMENT '书编号',
+b_name VARCHAR(50) NOT NULL UNIQUE COMMENT '书名',
+authors VARCHAR(100) NOT NULL UNIQUE COMMENT '作者',
+price FLOAT NOT NULL UNIQUE COMMENT '价格',
+pubdate YEAR NOT NULL UNIQUE COMMENT '出版日期',
+note VARCHAR(100) NOT NULL UNIQUE COMMENT '说明',
+num INT(11) NOT NULL UNIQUE COMMENT '库存'
+);
+-- | 字段名  | 字段说明 | 数据类型      | 允许为空 | 唯一 |
+-- | ------- | -------- | ------------- | -------- | ---- |
+-- | b_id    | 书编号   | int(11)       | 否       | 是   |
+-- | b_name  | 书名     | varchar（50） | 否       | 否   |
+-- | authors | 作者     | varchar(100)  | 否       | 否   |
+-- | price   | 价格     | float         | 否       | 否   |
+-- | pubdate | 出版日期 | year          | 否       | 否   |
+-- | note    | 说明     | varchar(100)  | 是       | 否   |
+-- | num     | 库存     | int(11)       | 否       | 否   |
+-- 
+-- 3、向books表中插入记录
+--
+-- 1） 指定所有字段名称插入第一条记录
+INSERT INTO books(b_id,b_name,authors,price,pubdate,note,num) VALUES(1,'Tal of AAA','Dickes',23,1995,'novel',11);
+-- 2）不指定字段名称插入第二记录
+INSERT INTO books(b_id,b_name,authors,price,pubdate,note,num) VALUES(2,'Emmat','Jane lura',35,1993,'joke',22)
+-- 3）同时插入多条记录（剩下的所有记录）
+-- 
+-- | b_id | b_name        | authors         | price | pubdate | note     | num  |
+-- | ---- | ------------- | --------------- | ----- | ------- | -------- | ---- |
+-- | 1    | Tal of AAA    | Dickes          | 23    | 1995    | novel    | 11   |
+-- | 2    | EmmaT         | Jane lura       | 35    | 1993    | joke     | 22   |
+-- | 3    | Story of Jane | Jane Tim        | 40    | 2001    | novel    | 0    |
+-- | 4    | Lovey Day     | George Byron    | 20    | 2005    | novel    | 30   |
+-- | 5    | Old land      | Honore Blade    | 30    | 2010    | law      | 0    |
+-- | 6    | The Battle    | Upton Sara      | 30    | 1999    | medicine | 40   |
+-- | 7    | Rose Hood     | Richard haggard | 28    | 2008    | cartoon  | 28   |
+INSERT INTO books VALUES(3,'Story of Jane','Jane Tim',35,2001,'novel',0),
+(4,'Lovey Day','George Byron',20,2005,'novel',30),
+(5,'Old land','Honore Blade',30,2010,'law',0),
+(6,'The Battle','Upton Sara',30,1999,'meducine',28),
+(7,'Rose Hood','Richard haggard',28,2008,'cartoon',28);
+
+-- 4、将小说类型(novel)的书的价格都增加5。
+UPDATE books SET price = price + 5 WHERE note = 'novel';
+-- 5、将名称为EmmaT的书的价格改为40。
+UPDATE books SET price = price + 5 WHERE b_name = 'Emmat';
+-- 6、删除库存为0的记录
+DELETE FROM books WHERE num = 0;
+
+-- ```mysql
+-- 
+-- ```
+-- 
+-- 
+-- 
+-- ## 第3题
+-- 
+-- 1、创建数据库test03_bookstore
+CREATE DATABASE test03_bookstore;
+-- 2、创建book表
+create database test03_bookstore; USE test03_bookstore; create table book( id int(11) primary key auto_increment, title varchar(100) not null , author varchar(100) not null, price double(11,2) not null, sales int(11) not null, stock int(11) not null, img_path varchar(100) not null );
+-- ```mysql
+-- +----------+--------------+------+-----+---------+----------------+
+-- | Field    | Type         | Null | Key | Default | Extra          |
+-- +----------+--------------+------+-----+---------+----------------+
+-- | id       | int(11)      | NO   | PRI | NULL    | auto_increment |
+-- | title    | varchar(100) | NO   |     | NULL    |                |
+-- | author   | varchar(100) | NO   |     | NULL    |                |
+-- | price    | double(11,2) | NO   |     | NULL    |                |
+-- | sales    | int(11)      | NO   |     | NULL    |                |
+-- | stock    | int(11)      | NO   |     | NULL    |                |
+-- | img_path | varchar(100) | NO   |     | NULL    |                |
+-- +----------+--------------+------+-----+---------+----------------+
+-- ```
+-- 
+-- 尝试添加部分模拟数据，参考示例如下：
+-- 
+-- ```mysql
+-- +----+-------------+------------+-------+-------+-------+----------------------------+
+-- | id | title       | author     | price | sales | stock | img_path                   |
+-- +----+-------------+------------+-------+-------+-------+-----------------------------+
+-- |  1 | 解忧杂货店    | 东野圭吾   | 27.20 |   102 |    98 | upload/books/解忧杂货店.jpg   |
+-- |  2 | 边城         | 沈从文     | 23.00 |   102 |    98 | upload/books/边城.jpg       |
+-- +----+---------------+------------+-------+-------+-------+----------------------------+
+-- ```
+insert book values (1,'解忧杂货店','东野圭吾',27.20,102,98,'upload/books/解忧杂货店.jpg'),
+
+(2,'边城','沈从文',23.00,102,98,'upload/books/边城.jpg');
+-- 3、创建用户表users，并插入数据
+create users( id int(11) primary key auto_increment, username varchar(100) not null unique , password varchar(100) not null , email varchar(100) );
+-- ```mysql
+-- +----------+--------------+------+-----+---------+----------------+
+-- | Field    | Type         | Null | Key | Default | Extra          |
+-- +----------+--------------+------+-----+---------+----------------+
+-- | id       | int(11)      | NO   | PRI | NULL    | auto_increment |
+-- | username | varchar(100) | NO   | UNI | NULL    |                |
+-- | password | varchar(100) | NO   |     | NULL    |                |
+-- | email    | varchar(100) | YES  |     | NULL    |                |
+-- +----------+--------------+------+-----+---------+----------------+
+-- ```
+
+-- 尝试添加部分模拟数据，参考示例如下：
+-- 
+-- ```mysql
+-- +----+----------+----------------------------------+--------------------+
+-- | id | username | password                         | email              |
+-- +----+----------+----------------------------------+--------------------+
+-- |  1 | admin    | 112233                           | admin@mxdx.com     |
+-- +----+----------+----------------------------------+--------------------+
+-- ```
+insert users values (1,'admin','112233','admin@mxdx.com' );
+
+
+-- 4、创建订单表orders
+-- 
+-- ```mysql
+-- +--------------+--------------+------+-----+---------+-------+
+-- | Field        | Type         | Null | Key | Default | Extra |
+-- +--------------+--------------+------+-----+---------+-------+
+-- | id           | varchar(100) | NO   | PRI | NULL    |       |
+-- | order_time   | datetime     | NO   |     | NULL    |       |
+-- | total_count  | int(11)      | NO   |     | NULL    |       |
+-- | total_amount | double(11,2) | NO   |     | NULL    |       |
+-- | state        | int(11)      | NO   |     | NULL    |       |
+-- | user_id      | int(11)      | NO   | MUL | NULL    |       |
+-- +--------------+--------------+------+-----+---------+-------+
+-- ```
+create table orders( id varchar(100) primary key , order_time datetime not null , total_count int(11) not null , total_amount double(11,2) not null , state int(11) not null , user_id int(11) not null ); alter table orders add index (user_id);
+-- 尝试添加部分模拟数据，参考示例如下：
+-- 
+-- ```mysql
+-- +----------------+---------------------+-------------+--------------+-------+---------+
+-- | id             | order_time          | total_count | total_amount | state | user_id |
+-- +----------------+---------------------+-------------+--------------+-------+---------+
+-- | 15294258455691 | 2018-06-20 00:30:45 |           2 |        50.20 |     0 |       1 |
+-- +----------------+---------------------+-------------+--------------+-------+---------+
+-- ```
+insert into orders values ('15294258455691 ','2018-06-20 00:30:45',2,50.20,0,1);
+-- 5、创建订单明细表order_items
+-- 
+-- ```mysql
+-- +----------+--------------+------+-----+---------+----------------+
+-- | Field    | Type         | Null | Key | Default | Extra          |
+-- +----------+--------------+------+-----+---------+----------------+
+-- | id       | int(11)      | NO   | PRI | NULL    | auto_increment |
+-- | count    | int(11)      | NO   |     | NULL    |                |
+-- | amount   | double(11,2) | NO   |     | NULL    |                |
+-- | title    | varchar(100) | NO   |     | NULL    |                |
+-- | author   | varchar(100) | NO   |     | NULL    |                |
+-- | price    | double(11,2) | NO   |     | NULL    |                |
+-- | img_path | varchar(100) | NO   |     | NULL    |                |
+-- | order_id | varchar(100) | NO   | MUL | NULL    |                |
+-- +----------+--------------+------+-----+---------+----------------+
+-- ```
+create table order_items( id int(11) primary key auto_increment, count int(11) not null , amount double(11,2) not null , title varchar(100) not null , author varchar(100)not null , price double(11,2) not null , img_path varchar(100)not null , order_id varchar(100) not null ); alter table order_items add index (order_id); 
+-- 尝试添加部分模拟数据，参考示例如下：
+-- 
+-- ```mysql
+-- +----+-------+--------+---------+---------+-------+----------------+----------------+
+-- | id |count| amount| title    | author   | price | img_path       | order_id       |
+-- +----+-------+--------+------------+----------+-------+----------------+----------------+
+-- |  1 |   1 |  27.20| 解忧杂货店 | 东野圭吾 | 27.20 | static/img/default.jpg|15294258455691 |
+-- |  2 |   1 |  23.00| 边城      | 沈从文   | 23.00 | static/img/default.jpg|15294258455691 |
+-- +----+-------+--------+------------+----------+-------+------------+----------------+
+-- ```
+insert into order_items values (1,1,27.20,'解忧杂货店','东野圭吾',27.20,'static/img/default.jpg','15294258455691'), (2,1,23.00,'边城','沈从文',23.00,'static/img/default.jpg','15294258455691');
+-- 参考答案：
+~~~
+