diff --git "a/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test01_market.md" "b/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test01_market.md"
deleted file mode 100644
index 60bbbc18247efe6bf29e0042d575e710bcb3671d..0000000000000000000000000000000000000000
--- "a/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test01_market.md"	
+++ /dev/null
@@ -1,31 +0,0 @@
-#1、创建数据库test01_market
-CREATE database test01_market;
-use test01_market;
-#2、创建表格customers
-#| 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        |
-CREATE TABLE customers(
-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 COLUMN c_gender char(1);
-ALTER TABLE customers MODIFY c_gender char(1) AFTER c_name;
-#要求7：将表名改为customers_info
-ALTER TABLE customers RENAME TO customers_info;
-#要求8：删除字段c_city
-ALTER TABLE customers_info DROP COLUMN c_city;
\ No newline at end of file
diff --git "a/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test02_library(1).md" "b/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test02_library(1).md"
deleted file mode 100644
index fdf1167ce5f42ed3e56c23fb0d5cfe3b6447bc58..0000000000000000000000000000000000000000
--- "a/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test02_library(1).md"	
+++ /dev/null
@@ -1,49 +0,0 @@
-#1、创建数据库test02_library
-CREATE DATABASE test02_library;
-USE test02_library;
-#2、创建表格books
-CREATE TABLE books(
-b_id int(11) not null ,
-b_name VARCHAR(50) NOT NULL,
-`authors` VARCHAR(100) NOT NULL,
-price FLOAT NOT null ,
-pubdate year NOT NULL,
-note varchar(100) ,
-num int(11) not NULL
-);
-DESC books;
-#| 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);
-SELECT*FROM books;
-#2）不指定字段名称插入第二记录
-INSERT INTO books 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）
-INSERT INTO books VALUES(3,'Story of Jane','Jane Tim',40,'2001','novel',0),(4,'Lovey Day','George Byron',20,'2005','novel',30),(5,'Old land','Honore Byron',20,'2010','law',0),(6,'The Battle','Upton Sara',30,'1999','medicine',40),(7,'Rose Hood','Richard haggard',28,'2008','cartoon',28);
-SELECT*FROM books;
-#| 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   |
-
-#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=40 WHERE b_name='EmmaT';
-#6、删除库存为0的记录
-DELETE from books where num=0;
-SELECT*FROM books;
\ No newline at end of file
diff --git "a/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test03_bookstore.md" "b/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test03_bookstore.md"
deleted file mode 100644
index d957f1aaeefd34bd809afc662a8d757327226f99..0000000000000000000000000000000000000000
--- "a/17 \350\221\243\345\272\206\345\274\272/#1\343\200\201\345\210\233\345\273\272\346\225\260\346\215\256\345\272\223test03_bookstore.md"	
+++ /dev/null
@@ -1,123 +0,0 @@
-#1、创建数据库test03_bookstore
-CREATE DATABASE test03_booksore;
-USE test03_booksore;
-#2、创建book表
-#+----------+--------------+------+-----+---------+----------------+
-#| 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    |                |
-#+----------+--------------+------+-----+---------+----------------+
-CREATE TABLE book(
-id int(11) UNSIGNED auto_increment PRIMARY KEY not null,
-title VARCHAR(100) NOT NULL,
-`authors` 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
-);
-DESC book;
-#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 INTO book VALUES(1,'解忧杂货店','东野吾圭',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');
-SELECT*FROM book;
-
-#3、创建用户表users，并插入数据
-#+----------+--------------+------+-----+---------+----------------+
-#| 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    |                |
-#+----------+--------------+------+-----+---------+----------------+
-CREATE TABLE users(
-id INT(11) UNSIGNED auto_increment PRIMARY key NOT null,
-usersname VARCHAR(100) UNIQUE KEY NOT NULL,
-`password` VARCHAR(100) NOT null,
-email VARCHAR(100) NULL
-);
-DESC users;
-#尝试添加部分模拟数据，参考示例如下：
-#+----+----------+----------------------------------+--------------------+
-#| id | username | password                         | email              |
-#+----+----------+----------------------------------+--------------------+
-#|  1 | admin    | 112233                           | admin@mxdx.com     |
-#+----+----------+----------------------------------+--------------------+
-INSERT INTO users VALUES(1,'admin',112233,'admin@mxdx.com');
-SELECT*FROM users;
-
-#4、创建订单表orders
-#+--------------+--------------+------+-----+---------+-------+
-#| 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 NOT NULL,
-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 
-); 
-DESC orders;
-#尝试添加部分模拟数据，参考示例如下：
-#+----------------+---------------------+-------------+--------------+-------+---------+
-#| 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(152942258455691,'2018-06-20 00:30:45',2,50.20,0,1);
-SELECT*FROM orders;
-
-#5、创建订单明细表order_items
-#+----------+--------------+------+-----+---------+----------------+
-#| 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) UNSIGNED auto_increment PRIMARY key NOT null,
-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
-);
-DESC order_items;
-#尝试添加部分模拟数据，参考示例如下：
-#+----+-------+--------+---------+---------+-------+----------------+----------------+
-#| 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);
-SELECT*FROM order_items;
\ No newline at end of file
diff --git "a/17 \350\221\243\345\272\206\345\274\272/20220223\345\244\215\344\271\240.md" "b/17 \350\221\243\345\272\206\345\274\272/20220223\345\244\215\344\271\240.md"
new file mode 100644
index 0000000000000000000000000000000000000000..578eaee3cc3224a7abff310c7b9912611cc9bf1f
--- /dev/null
+++ "b/17 \350\221\243\345\272\206\345\274\272/20220223\345\244\215\344\271\240.md"	
@@ -0,0 +1,25 @@
+**常用函数**
+
+AVG(x) ：求平均值
+
+SUM(x)：求总和
+
+MAX(x)：求最大值
+
+MIN(x) ：求最小值
+
+COUNT(x) ：统计记录数
+
+**数学函数**
+
+ABS(X) 返回x的绝对值
+
+CEIL(x)返回大于x的最小整数值
+
+FLOOR（x）返回小于x的最大
+
+mod用于两数的模
+
+rand   随机数
+
+
diff --git "a/17 \350\221\243\345\272\206\345\274\272/202302022\350\277\220\347\256\227\347\254\246.md" "b/17 \350\221\243\345\272\206\345\274\272/202302022\350\277\220\347\256\227\347\254\246.md"
deleted file mode 100644
index 10dcfd853e9d41ae54c1f2eeabb1a047da2a5f2e..0000000000000000000000000000000000000000
--- "a/17 \350\221\243\345\272\206\345\274\272/202302022\350\277\220\347\256\227\347\254\246.md"	
+++ /dev/null
@@ -1,89 +0,0 @@
-# 笔记
-
-```mysql
-select 字段 as 命名 from 表名 #临时命名字段
-
-select 字段1 运算符 字段2 as 命名 from 表名 #重新命名运算后的字段
-
-select * from 表名 where 条件  #查询条件字段
-
-select* from 表名 where 字段 like '%字符%' #搜素指定字符的字段
-```
-
-# 作业
-
-```mysql
-create database class11 CHARSET utf8;
-use class11;
-CREATE TABLE employee(
-id int,
-`name` varchar(20),
-sex varchar(20),
-tel varchar(20),
-addr varchar(50),
-salary FLOAT
-);
-insert into employee values(10001,'张一一','男','13456789000','广东韶关',10010.58);
-insert into employee values(10002,'刘小红','女','13454319000','广东江门',12010.21);
-insert into employee VALUES(10003,'李四','男','0751-1234567','广东佛山',10040.11);
-insert into employee VALUES(10004,'刘小强','男','0755-5555555','广东深圳',15010.23);
-insert into employee VALUES(10005,'王艳','男',NULL,'广东广州',14050.16);
-select * from employee;
-#要求1：**查询出薪资在12000~13000之间的员工信息。
-select * from employee where salary >= 12000 and salary <=13000;
-#**要求2：**查询出姓“刘”的员工的工号，姓名，家庭住址。
-select id,`name`,addr from employee WHERE `name` like '刘%';
-#**要求3：**将“李四”的家庭住址改为“广东韶关”
-UPDATE employee set addr="广东昭关" where `name`='李四';
-#**要求4：**查询出名字中带“小”的员工
-select * from employee where `name` like '%小%';
-#**要求5：**查询出薪资高于11000的男员工信息
-select * from employee where salary>11000;
-#**要求6：**查询没有登记电话号码的员工
-select * from employee where tel is null;
-#**要求7：**查询薪资高于12000或者家是广东深圳、广州的男员工
-select * from employee where salary>12000 AND (addr='广东深圳' or addr= '广东广州') AND sex='男';
-#**要求8：**查询每个员工的年薪，显示“姓名、年薪”
-select `name` '姓名',salary '年薪' from employee;
-
-```
-
-```mysql
-CREATE TABLE countries_info(
-	`name` VARCHAR(100),
-	`continent` VARCHAR(100),
-	`area` INT,
-	population INT,
-	gdp BIGINT
-);
-desc countries_info;
-INSERT INTO countries_info VALUES('Afghanistan','Asia',652230,25500100,20343000000);
-INSERT INTO countries_info VALUES('Albania','Europe',28748,2831741,12960000000);
-INSERT INTO countries_info VALUES('Algeria','Africa',2381741,37100000,188681000000);
-INSERT INTO countries_info VALUES('Andorra','Europe',468,78115,3712000000);
-INSERT INTO countries_info VALUES('Angola','Africa',1246700,20609294,100990000000);
-select * from countries_info;
-#要求1：** 查询大国 的国家名称、人口和面积。
-select `name`,area,population from countries_info;
-#如果一个国家满足下述两个条件之一，则认为该国是 大国 ：
-#- 面积至少为 300万平方公里（即，3000000 km2）
-select * from countries_info where area>=3000000;
-#- 人口至少为 2500 万（即 25000000）
-select * from countries_info where population>=25000000;
-#**要求2：**查询属于亚洲的国家名称、所属大陆、面积、人口和 GDP 值
-select * from countries_info where continent='Asia';
-#**要求3：**查询国土面积不足1万平方公里且人口不走10万人的国家信息
-select * from countries_info where area <10000 and population <100000;
-#**要求4：**查询国家名字中包含“o“字母的国家信息
-select * from countries_info where `name`like '%o%';
-#**要求5：**查询GDP值超过10000000000的国家信息
-select * from countries_info where gdp>10000000000;
-#**要求6：**查询每个国家的人均贡献GDP值（GDP/人口总数）并显示为“国家名、人口、GDP值、人均贡献GDP值”
-select  continent,population,gdp, gdp/population as '人均GDP' from countries_info;
-#**要求7：**查询人均贡献GDP值低于1000的国家信息。
-select  gdp/population as "人均GDP" from countries_info where (gdp/population)<1000;
-#**要求8：**查询每个国家的人均国土面积（面积/人口总数）并显示为“国家名、面积、人口、人均国土面积值”
-    select  continent,area,population,area/population as '人均国土面积' from countries_info;
-```
-
-
diff --git "a/17 \350\221\243\345\272\206\345\274\272/20230213\345\256\211\350\243\205.md" "b/17 \350\221\243\345\272\206\345\274\272/20230213\345\256\211\350\243\205.md"
new file mode 100644
index 0000000000000000000000000000000000000000..34f89e4569ec723b3ad6adfbc8ccdfa88df387b1
--- /dev/null
+++ "b/17 \350\221\243\345\272\206\345\274\272/20230213\345\256\211\350\243\205.md"	
@@ -0,0 +1,13 @@
+在mysql网站上下载mysql5,7然后进入数据库安装界面。
+
+下载完成后进入任务管理器点开服务界面，找到mysql服务将它设为自动并开启。
+
+对此电脑右击进入属性选择高级管理进入环境变量中找到path变量将mysql路径输入C:\Program Files\MySQL\MySQL Server 5.7\bin。
+
+使用win+r输入cmd进入管理员界面输入mysql出现以下代码表示安装成功
+
+mysql -u root -p
+
+密码 root
+
+
diff --git "a/17 \350\221\243\345\272\206\345\274\272/20230221 \344\270\252\344\272\272\344\273\213\347\273\215.md" "b/17 \350\221\243\345\272\206\345\274\272/20230215 \344\270\252\344\272\272\344\273\213\347\273\215.md"
similarity index 100%
rename from "17 \350\221\243\345\272\206\345\274\272/20230221 \344\270\252\344\272\272\344\273\213\347\273\215.md"
rename to "17 \350\221\243\345\272\206\345\274\272/20230215 \344\270\252\344\272\272\344\273\213\347\273\215.md"
diff --git "a/17 \350\221\243\345\272\206\345\274\272/20230221DDL\345\222\214DML.md" "b/17 \350\221\243\345\272\206\345\274\272/20230216DDL\345\222\214DML.md"
similarity index 100%
rename from "17 \350\221\243\345\272\206\345\274\272/20230221DDL\345\222\214DML.md"
rename to "17 \350\221\243\345\272\206\345\274\272/20230216DDL\345\222\214DML.md"
diff --git "a/17 \350\221\243\345\272\206\345\274\272/20230221 \347\272\246\346\235\237.md" "b/17 \350\221\243\345\272\206\345\274\272/20230220 \347\272\246\346\235\237.md"
similarity index 100%
rename from "17 \350\221\243\345\272\206\345\274\272/20230221 \347\272\246\346\235\237.md"
rename to "17 \350\221\243\345\272\206\345\274\272/20230220 \347\272\246\346\235\237.md"