阿里云轻量应用服务器Linux-Centos7下MySQL8.0.19的使用

news2024/10/6 18:32:40

初始环境：阿里云轻量应用服务器已经安装MySQL8.0.19
具体目标：使用MySQL 8.0.19

目录

  • 第一步：初始化
  • 第二步：创建一些表
  • 第三步：添加一些数据
  • 第四步：详情一览
  • 第五步：检索数据
  • 第六步：排序检索数据
  • 第七步：过滤数据
  • 第八步：高级数据过滤
  • 第九步：用通配符进行过滤
  • 第十步：创建计算字段
  • 第十一步：使用函数处理数据
  • 第十二步：汇总数据
  • 第十三步：分组数据
  • 第十四步：使用子查询
  • 第十五步：创建联结
  • 第十六步：创建高级联结
  • 第十七步：组合查询
  • 第十八步：插入数据
  • 第十九步：更新和删除数据
  • 第二十步：创建和操纵表
  • 第二十一步：使用视图

第一步：初始化

1.进入数据库，然后输入密码123456

mysql -u root -p

2.创建数据库

create database test;

3.使用数据库

use test;

第二步：创建一些表

1.创建表Customers

CREATE TABLE Customers
(
  cust_id      char(10)  NOT NULL ,
  cust_name    char(50)  NOT NULL ,
  cust_address char(50)  NULL ,
  cust_city    char(50)  NULL ,
  cust_state   char(5)   NULL ,
  cust_zip     char(10)  NULL ,
  cust_country char(50)  NULL ,
  cust_contact char(50)  NULL ,
  cust_email   char(255) NULL 
);

2.创建表OrderItems

CREATE TABLE OrderItems
(
  order_num  int          NOT NULL ,
  order_item int          NOT NULL ,
  prod_id    char(10)     NOT NULL ,
  quantity   int          NOT NULL ,
  item_price decimal(8,2) NOT NULL 
);

3.创建表Orders

CREATE TABLE Orders
(
  order_num  int      NOT NULL ,
  order_date datetime NOT NULL ,
  cust_id    char(10) NOT NULL 
);

4.创建表Products

CREATE TABLE Products
(
  prod_id    char(10)      NOT NULL ,
  vend_id    char(10)      NOT NULL ,
  prod_name  char(255)     NOT NULL ,
  prod_price decimal(8,2)  NOT NULL ,
  prod_desc  text          NULL 
);

5.创建表Vendors

CREATE TABLE Vendors
(
  vend_id      char(10) NOT NULL ,
  vend_name    char(50) NOT NULL ,
  vend_address char(50) NULL ,
  vend_city    char(50) NULL ,
  vend_state   char(5)  NULL ,
  vend_zip     char(10) NULL ,
  vend_country char(50) NULL 
);

6.定义主键

ALTER TABLE Customers ADD PRIMARY KEY (cust_id);
ALTER TABLE OrderItems ADD PRIMARY KEY (order_num, order_item);
ALTER TABLE Orders ADD PRIMARY KEY (order_num);
ALTER TABLE Products ADD PRIMARY KEY (prod_id);
ALTER TABLE Vendors ADD PRIMARY KEY (vend_id);

7.定义外键

ALTER TABLE OrderItems ADD CONSTRAINT FK_OrderItems_Orders FOREIGN KEY (order_num) REFERENCES Orders (order_num);
ALTER TABLE OrderItems ADD CONSTRAINT FK_OrderItems_Products FOREIGN KEY (prod_id) REFERENCES Products (prod_id);
ALTER TABLE Orders ADD CONSTRAINT FK_Orders_Customers FOREIGN KEY (cust_id) REFERENCES Customers (cust_id);
ALTER TABLE Products ADD CONSTRAINT FK_Products_Vendors FOREIGN KEY (vend_id) REFERENCES Vendors (vend_id);

第三步：添加一些数据

1.给表Customers添加数据

INSERT INTO Customers(cust_id, cust_name, cust_address, cust_city, cust_state, cust_zip, cust_country, cust_contact, cust_email)
VALUES('1000000001', 'Village Toys', '200 Maple Lane', 'Detroit', 'MI', '44444', 'USA', 'John Smith', 'sales@villagetoys.com');
INSERT INTO Customers(cust_id, cust_name, cust_address, cust_city, cust_state, cust_zip, cust_country, cust_contact)
VALUES('1000000002', 'Kids Place', '333 South Lake Drive', 'Columbus', 'OH', '43333', 'USA', 'Michelle Green');
INSERT INTO Customers(cust_id, cust_name, cust_address, cust_city, cust_state, cust_zip, cust_country, cust_contact, cust_email)
VALUES('1000000003', 'Fun4All', '1 Sunny Place', 'Muncie', 'IN', '42222', 'USA', 'Jim Jones', 'jjones@fun4all.com');
INSERT INTO Customers(cust_id, cust_name, cust_address, cust_city, cust_state, cust_zip, cust_country, cust_contact, cust_email)
VALUES('1000000004', 'Fun4All', '829 Riverside Drive', 'Phoenix', 'AZ', '88888', 'USA', 'Denise L. Stephens', 'dstephens@fun4all.com');
INSERT INTO Customers(cust_id, cust_name, cust_address, cust_city, cust_state, cust_zip, cust_country, cust_contact)
VALUES('1000000005', 'The Toy Store', '4545 53rd Street', 'Chicago', 'IL', '54545', 'USA', 'Kim Howard');

2.给表Vendors添加数据

INSERT INTO Vendors(vend_id, vend_name, vend_address, vend_city, vend_state, vend_zip, vend_country)
VALUES('BRS01','Bears R Us','123 Main Street','Bear Town','MI','44444', 'USA');
INSERT INTO Vendors(vend_id, vend_name, vend_address, vend_city, vend_state, vend_zip, vend_country)
VALUES('BRE02','Bear Emporium','500 Park Street','Anytown','OH','44333', 'USA');
INSERT INTO Vendors(vend_id, vend_name, vend_address, vend_city, vend_state, vend_zip, vend_country)
VALUES('DLL01','Doll House Inc.','555 High Street','Dollsville','CA','99999', 'USA');
INSERT INTO Vendors(vend_id, vend_name, vend_address, vend_city, vend_state, vend_zip, vend_country)
VALUES('FRB01','Furball Inc.','1000 5th Avenue','New York','NY','11111', 'USA');
INSERT INTO Vendors(vend_id, vend_name, vend_address, vend_city, vend_state, vend_zip, vend_country)
VALUES('FNG01','Fun and Games','42 Galaxy Road','London', NULL,'N16 6PS', 'England');
INSERT INTO Vendors(vend_id, vend_name, vend_address, vend_city, vend_state, vend_zip, vend_country)
VALUES('JTS01','Jouets et ours','1 Rue Amusement','Paris', NULL,'45678', 'France');

3.给表Products添加数据

INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('BR01', 'BRS01', '8 inch teddy bear', 5.99, '8 inch teddy bear, comes with cap and jacket');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('BR02', 'BRS01', '12 inch teddy bear', 8.99, '12 inch teddy bear, comes with cap and jacket');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('BR03', 'BRS01', '18 inch teddy bear', 11.99, '18 inch teddy bear, comes with cap and jacket');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('BNBG01', 'DLL01', 'Fish bean bag toy', 3.49, 'Fish bean bag toy, complete with bean bag worms with which to feed it');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('BNBG02', 'DLL01', 'Bird bean bag toy', 3.49, 'Bird bean bag toy, eggs are not included');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('BNBG03', 'DLL01', 'Rabbit bean bag toy', 3.49, 'Rabbit bean bag toy, comes with bean bag carrots');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('RGAN01', 'DLL01', 'Raggedy Ann', 4.99, '18 inch Raggedy Ann doll');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('RYL01', 'FNG01', 'King doll', 9.49, '12 inch king doll with royal garments and crown');
INSERT INTO Products(prod_id, vend_id, prod_name, prod_price, prod_desc)
VALUES('RYL02', 'FNG01', 'Queen doll', 9.49, '12 inch queen doll with royal garments and crown');

4.给表Orders添加数据

INSERT INTO Orders(order_num, order_date, cust_id)
VALUES(20005, '2012-05-01', '1000000001');
INSERT INTO Orders(order_num, order_date, cust_id)
VALUES(20006, '2012-01-12', '1000000003');
INSERT INTO Orders(order_num, order_date, cust_id)
VALUES(20007, '2012-01-30', '1000000004');
INSERT INTO Orders(order_num, order_date, cust_id)
VALUES(20008, '2012-02-03', '1000000005');
INSERT INTO Orders(order_num, order_date, cust_id)
VALUES(20009, '2012-02-08', '1000000001');

5.给表OrderItems添加数据

INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20005, 1, 'BR01', 100, 5.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20005, 2, 'BR03', 100, 10.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20006, 1, 'BR01', 20, 5.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20006, 2, 'BR02', 10, 8.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20006, 3, 'BR03', 10, 11.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20007, 1, 'BR03', 50, 11.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20007, 2, 'BNBG01', 100, 2.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20007, 3, 'BNBG02', 100, 2.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20007, 4, 'BNBG03', 100, 2.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20007, 5, 'RGAN01', 50, 4.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20008, 1, 'RGAN01', 5, 4.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20008, 2, 'BR03', 5, 11.99);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20008, 3, 'BNBG01', 10, 3.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20008, 4, 'BNBG02', 10, 3.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20008, 5, 'BNBG03', 10, 3.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20009, 1, 'BNBG01', 250, 2.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20009, 2, 'BNBG02', 250, 2.49);
INSERT INTO OrderItems(order_num, order_item, prod_id, quantity, item_price)
VALUES(20009, 3, 'BNBG03', 250, 2.49);

6.提交操作

commit;

第四步：详情一览

Customers 表：
在这里插入图片描述
Vendors 表：
在这里插入图片描述
Products 表：
在这里插入图片描述
Orders 表：
在这里插入图片描述
OrderItems 表：
在这里插入图片描述

第五步：检索数据

1.检索单个列：

SELECT prod_name 
FROM Products;

2.检索多个列：

SELECT prod_id, prod_name, prod_price 
FROM Products;

3.检索所有列：

SELECT * 
FROM Products;

4.检索不同的值：

SELECT vend_id 
FROM Products;

SELECT DISTINCT vend_id 
FROM Products;

5.限制结果：

SELECT prod_name 
FROM Products 
LIMIT 5;

SELECT prod_name 
FROM Products 
LIMIT 5 OFFSET 5;

6.使用注释：

SELECT prod_name -- 这是一条注释 
FROM Products;

# 这是一条注释
SELECT prod_name 
FROM Products;

/* SELECT prod_name, vend_id
FROM Products; */
SELECT prod_name 
FROM Products;

第六步：排序检索数据

1.排序数据

SELECT prod_name 
FROM Products;

SELECT prod_name 
FROM Products 
ORDER BY prod_name;

2.按多个列排序

SELECT prod_id, prod_price, prod_name 
FROM Products
ORDER BY prod_price, prod_name;

3.按列位置排序

SELECT prod_id, prod_price, prod_name 
FROM Products 
ORDER BY 2, 3;

4.指定排序方向

SELECT prod_id, prod_price, prod_name 
FROM Products 
ORDER BY prod_price DESC;

SELECT prod_id, prod_price, prod_name 
FROM Products 
ORDER BY prod_price DESC, prod_name;

第七步：过滤数据

1.使用 WHERE 子句

SELECT prod_name, prod_price 
FROM Products 
WHERE prod_price = 3.49;

2.检查单个值：

SELECT prod_name, prod_price 
FROM Products 
WHERE prod_price < 10;

SELECT prod_name, prod_price 
FROM Products 
WHERE prod_price <= 10;

3.不匹配检查：

SELECT vend_id, prod_name 
FROM Products 
WHERE vend_id <> 'DLL01';

SELECT vend_id, prod_name 
FROM Products 
WHERE vend_id != 'DLL01';

4.范围值检查：

SELECT prod_name, prod_price 
FROM Products 
WHERE prod_price BETWEEN 5 AND 10;

5.空值检查：

SELECT prod_name 
FROM Products 
WHERE prod_price IS NULL;

SELECT cust_name 
FROM Customers 
WHERE cust_email IS NULL;

第八步：高级数据过滤

1.AND 操作符

SELECT prod_id, prod_price, prod_name 
FROM Products 
WHERE vend_id = 'DLL01' AND prod_price <= 4;

2.OR 操作符

SELECT prod_name, prod_price 
FROM Products 
WHERE vend_id = 'DLL01' OR vend_id = 'BRS01';

3.求值顺序

SELECT prod_name, prod_price 
FROM Products 
WHERE vend_id = 'DLL01' OR vend_id = 'BRS01' AND prod_price >= 10;

SELECT prod_name, prod_price 
FROM Products 
WHERE (vend_id = 'DLL01' OR vend_id = 'BRS01') AND prod_price >= 10;

4.IN 操作符

SELECT prod_name, prod_price 
FROM Products 
WHERE vend_id IN ( 'DLL01', 'BRS01' ) ORDER BY prod_name;

SELECT prod_name, prod_price 
FROM Products 
WHERE vend_id = 'DLL01' OR vend_id = 'BRS01' ORDER BY prod_name;

5.NOT 操作符

SELECT prod_name 
FROM Products 
WHERE NOT vend_id = 'DLL01' 
ORDER BY prod_name;

SELECT prod_name 
FROM Products 
WHERE vend_id <> 'DLL01' 
ORDER BY prod_name;

第九步：用通配符进行过滤

1.百分号（%）通配符

SELECT prod_id, prod_name 
FROM Products 
WHERE prod_name LIKE 'Fish%';

SELECT prod_id, prod_name 
FROM Products 
WHERE prod_name LIKE '%bean bag%';

SELECT prod_name 
FROM Products 
WHERE prod_name LIKE 'F%y';

2.下划线（_）通配符

SELECT prod_id, prod_name 
FROM Products 
WHERE prod_name LIKE '__ inch teddy bear';

SELECT prod_id, prod_name 
FROM Products 
WHERE prod_name LIKE '% inch teddy bear';

第十步：创建计算字段

1.拼接字段

SELECT Concat(vend_name, ' (', vend_country, ')') 
FROM Vendors 
ORDER BY vend_name;

SELECT Concat(RTRIM(vend_name) ,' (' ,RTRIM(vend_country) ,')') 
FROM Vendors 
ORDER BY vend_name;

2.使用别名：

SELECT Concat(vend_name, ' (', vend_country, ')') AS vend_title 
FROM Vendors 
ORDER BY vend_name;

3.执行算术计算：

SELECT prod_id, quantity, item_price 
FROM OrderItems 
WHERE order_num = 20008;

SELECT prod_id, quantity, item_price, quantity*item_price AS expanded_price 
FROM OrderItems 
WHERE order_num = 20008;

第十一步：使用函数处理数据

1.文本处理函数：

SELECT vend_name, UPPER(vend_name) AS vend_name_upcase 
FROM Vendors 
ORDER BY vend_name;

SELECT cust_name, cust_contact 
FROM Customers 
WHERE cust_contact = 'Michael Green';

SELECT cust_name, cust_contact 
FROM Customers 
WHERE SOUNDEX(cust_contact) = SOUNDEX('Michael Green');

2.日期和时间处理函数：

SELECT order_num 
FROM Orders 
WHERE YEAR(order_date) = 2012;

第十二步：汇总数据

1.AVG() 函数

SELECT AVG(prod_price) AS avg_price 
FROM Products;

SELECT AVG(prod_price) AS avg_price 
FROM Products 
WHERE vend_id = 'DLL01';

2.COUNT() 函数

SELECT COUNT(*) AS num_cust 
FROM Customers;

SELECT COUNT(cust_email) AS num_cust 
FROM Customers;

3.MAX() 函数

SELECT MAX(prod_price) AS max_price 
FROM Products;

4.MIN() 函数

SELECT MIN(prod_price) AS min_price 
FROM Products;

5.SUM() 函数

SELECT SUM(quantity) AS items_ordered 
FROM OrderItems 
WHERE order_num = 20005;

SELECT SUM(item_price*quantity) AS total_price 
FROM OrderItems 
WHERE order_num = 20005;

6.聚集不同值

SELECT AVG(DISTINCT prod_price) AS avg_price 
FROM Products 
WHERE vend_id = 'DLL01';

7.组合聚集函数

SELECT COUNT(*) AS num_items, MIN(prod_price) AS price_min, MAX(prod_price) AS price_max, AVG(prod_price) AS price_avg 
FROM Products;

第十三步：分组数据

1.数据分组

SELECT COUNT(*) AS num_prods 
FROM Products 
WHERE vend_id = 'DLL01';

2.创建分组

SELECT vend_id, COUNT(*) AS num_prods 
FROM Products 
GROUP BY vend_id;

3.过滤分组

SELECT cust_id, COUNT(*) AS orders 
FROM Orders 
GROUP BY cust_id 
HAVING COUNT(*) >= 2;

SELECT vend_id, COUNT(*) AS num_prods 
FROM Products 
WHERE prod_price >= 4 
GROUP BY vend_id 
HAVING COUNT(*) >= 2;

SELECT vend_id, COUNT(*) AS num_prods 
FROM Products 
GROUP BY vend_id 
HAVING COUNT(*) >= 2;

4.分组和排序

SELECT order_num, COUNT(*) AS items
FROM OrderItems
GROUP BY order_num
HAVING COUNT(*) >= 3;

SELECT order_num, COUNT(*) AS items
FROM OrderItems
GROUP BY order_num
HAVING COUNT(*) >= 3
ORDER BY items, order_num;

第十四步：使用子查询

1.利用子查询进行过滤

SELECT order_num
FROM OrderItems
WHERE prod_id = 'RGAN01';

SELECT cust_id
FROM Orders
WHERE order_num IN (20007,20008);

SELECT cust_id
FROM Orders
WHERE order_num IN (SELECT order_num
FROM OrderItems
WHERE prod_id = 'RGAN01');

SELECT cust_name, cust_contact
FROM Customers
WHERE cust_id IN ('1000000004','1000000005');

SELECT cust_name, cust_contact
FROM Customers
WHERE cust_id IN (SELECT cust_id
FROM Orders
WHERE order_num IN (SELECT order_num
FROM OrderItems
WHERE prod_id = 'RGAN01'));

2.作为计算字段使用子查询

SELECT COUNT(*) AS orders
FROM Orders
WHERE cust_id = '1000000001';

SELECT cust_name,
cust_state,
(SELECT COUNT(*)
FROM Orders
WHERE Orders.cust_id = Customers.cust_id) AS orders
FROM Customers
ORDER BY cust_name;

SELECT cust_name,
cust_state,
(SELECT COUNT(*)
FROM Orders
WHERE cust_id = cust_id) AS orders
FROM Customers
ORDER BY cust_name;

第十五步：创建联结

1.创建联结

SELECT vend_name, prod_name, prod_price
FROM Vendors, Products
WHERE Vendors.vend_id = Products.vend_id;

2.WHERE 子句的重要性

SELECT vend_name, prod_name, prod_price
FROM Vendors, Products;

3.内联结

SELECT vend_name, prod_name, prod_price
FROM Vendors INNER JOIN Products
ON Vendors.vend_id = Products.vend_id;

4.联结多个表

SELECT prod_name, vend_name, prod_price, quantity
FROM OrderItems, Products, Vendors
WHERE Products.vend_id = Vendors.vend_id
AND OrderItems.prod_id = Products.prod_id
AND order_num = 20007;

SELECT cust_name, cust_contact
FROM Customers
WHERE cust_id IN (SELECT cust_id
FROM Orders
WHERE order_num IN (SELECT order_num
FROM OrderItems
WHERE prod_id = 'RGAN01'));

SELECT cust_name, cust_contact
FROM Customers, Orders, OrderItems
WHERE Customers.cust_id = Orders.cust_id
AND OrderItems.order_num = Orders.order_num
AND prod_id = 'RGAN01';

第十六步：创建高级联结

1.使用表别名

SELECT Concat(RTRIM(vend_name), ' (', RTRIM(vend_country), ')')
AS vend_title
FROM Vendors
ORDER BY vend_name;

SELECT cust_name, cust_contact
FROM Customers AS C, Orders AS O, OrderItems AS OI
WHERE C.cust_id = O.cust_id
AND OI.order_num = O.order_num
AND prod_id = 'RGAN01';

2.自联结

SELECT cust_id, cust_name, cust_contact
FROM Customers
WHERE cust_name = (SELECT cust_name
FROM Customers
WHERE cust_contact = 'Jim Jones');

SELECT c1.cust_id, c1.cust_name, c1.cust_contact
FROM Customers AS c1, Customers AS c2
WHERE c1.cust_name = c2.cust_name
AND c2.cust_contact = 'Jim Jones';

3.自然联结

SELECT C.*, O.order_num, O.order_date,
OI.prod_id, OI.quantity, OI.item_price
FROM Customers AS C, Orders AS O, OrderItems AS OI
WHERE C.cust_id = O.cust_id
AND OI.order_num = O.order_num
AND prod_id = 'RGAN01';

4.外联结

SELECT Customers.cust_id, Orders.order_num
FROM Customers INNER JOIN Orders
ON Customers.cust_id = Orders.cust_id;

SELECT Customers.cust_id, Orders.order_num
FROM Customers LEFT OUTER JOIN Orders
ON Customers.cust_id = Orders.cust_id;

SELECT Customers.cust_id, Orders.order_num
FROM Customers RIGHT OUTER JOIN Orders
ON Orders.cust_id = Customers.cust_id;

5.使用带聚集函数的联结

SELECT Customers.cust_id,
COUNT(Orders.order_num) AS num_ord
FROM Customers INNER JOIN Orders
ON Customers.cust_id = Orders.cust_id
GROUP BY Customers.cust_id;

SELECT Customers.cust_id,
COUNT(Orders.order_num) AS num_ord
FROM Customers LEFT OUTER JOIN Orders
ON Customers.cust_id = Orders.cust_id
GROUP BY Customers.cust_id;

第十七步：组合查询

1.使用 UNION

SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_state IN ('IL','IN','MI');

SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_name = 'Fun4All';

SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_state IN ('IL','IN','MI')
UNION
SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_name = 'Fun4All';

SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_state IN ('IL','IN','MI')
OR cust_name = 'Fun4All';

2.包含或取消重复的行

SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_state IN ('IL','IN','MI')
UNION ALL
SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_name = 'Fun4All';

3.对组合查询结果排序

SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_state IN ('IL','IN','MI')
UNION
SELECT cust_name, cust_contact, cust_email
FROM Customers
WHERE cust_name = 'Fun4All'
ORDER BY cust_name, cust_contact;

第十八步：插入数据

1.插入完整的行

INSERT INTO Customers
VALUES('1000000006',
'Toy Land',
'123 Any Street',
'New York',
'NY',
'11111',
'USA',
NULL,
NULL);

INSERT INTO Customers(cust_id,
cust_name,
cust_address,
cust_city,
cust_state,
cust_zip,
cust_country,
cust_contact,
cust_email)
VALUES('1000000006',
'Toy Land',
'123 Any Street',
'New York',
'NY',
'11111',
'USA',
NULL,
NULL);

INSERT INTO Customers(cust_id,
cust_contact,
cust_email,
cust_name,
cust_address,
cust_city,
cust_state,
cust_zip)
VALUES('1000000006',
NULL,
NULL,
'Toy Land',
'123 Any Street',
'New York',
'NY',
'11111');

2.插入部分行

INSERT INTO Customers(cust_id,
cust_name,
cust_address,
cust_city,
cust_state,
cust_zip,
cust_country)
VALUES('1000000007',
'Toy Land',
'123 Any Street',
'New York',
'NY',
'11111',
'USA');

3.从一个表复制到另一个表

CREATE TABLE CustCopy AS
SELECT * FROM Customers;

4.插入检索出的数据

DELETE FROM CustCopy; 

INSERT INTO Customers(cust_id,
cust_contact,
cust_email,
cust_name,
cust_address,
cust_city,
cust_state,
cust_zip,
cust_country)
SELECT cust_id,
cust_contact,
cust_email,
cust_name,
cust_address,
cust_city,
cust_state,
cust_zip,
cust_country
FROM CustCopy;

第十九步：更新和删除数据

1.更新数据

UPDATE Customers
SET cust_email = 'kim@thetoystore.com'
WHERE cust_id = '1000000005';

UPDATE Customers
SET cust_contact = 'Sam Roberts',
cust_email = 'sam@toyland.com'
WHERE cust_id = '1000000006';

UPDATE Customers
SET cust_email = NULL
WHERE cust_id = '1000000005';

2.删除数据

DELETE FROM Customers
WHERE cust_id = '1000000007';

第二十步：创建和操纵表

1.表创建基础

CREATE TABLE ProductsNew
(
prod_id CHAR(10) NOT NULL,
vend_id CHAR(10) NOT NULL,
prod_name CHAR(254) NOT NULL,
prod_price DECIMAL(8,2) NOT NULL,
prod_desc VARCHAR(1000) NULL
);

2.使用 NULL 值

CREATE TABLE OrdersNew
(
order_num INTEGER NOT NULL,
order_date DATETIME NOT NULL,
cust_id CHAR(10) NOT NULL
);

CREATE TABLE VendorsNew
(
vend_id CHAR(10) NOT NULL,
vend_name CHAR(50) NOT NULL,
vend_address CHAR(50) ,
vend_city CHAR(50) ,
vend_state CHAR(5) ,
vend_zip CHAR(10) ,
vend_country CHAR(50)
);

3.指定默认值

CREATE TABLE OrderItemsNew
(
order_num INTEGER NOT NULL,
order_item INTEGER NOT NULL,
prod_id CHAR(10) NOT NULL,
quantity INTEGER NOT NULL DEFAULT 1,
item_price DECIMAL(8,2) NOT NULL
);

4.更新表

ALTER TABLE Vendors
ADD vend_phone CHAR(20);

ALTER TABLE Vendors
DROP COLUMN vend_phone;

5.删除表

DROP TABLE CustCopy;

第二十一步：使用视图

1.利用视图简化复杂的联结

SELECT cust_name, cust_contact
FROM Customers, Orders, OrderItems
WHERE Customers.cust_id = Orders.cust_id
AND OrderItems.order_num = Orders.order_num
AND prod_id = 'RGAN01';

CREATE VIEW ProductCustomers AS
SELECT cust_name, cust_contact, prod_id
FROM Customers, Orders, OrderItems
WHERE Customers.cust_id = Orders.cust_id
AND OrderItems.order_num = Orders.order_num;

SELECT cust_name, cust_contact
FROM ProductCustomers
WHERE prod_id = 'RGAN01';

2.用视图重新格式化检索出的数据

SELECT Concat(RTRIM(vend_name) , ' (' , RTRIM(vend_country) , ')')
AS vend_title
FROM Vendors
ORDER BY vend_name;

CREATE VIEW VendorLocations AS
SELECT Concat(RTRIM(vend_name) , ' (' , RTRIM(vend_country) , ')')
AS vend_title
FROM Vendors;

SELECT *
FROM VendorLocations;

3.用视图过滤不想要的数据

CREATE VIEW CustomerEMailList AS
SELECT cust_id, cust_name, cust_email
FROM Customers
WHERE cust_email IS NOT NULL;

SELECT *
FROM CustomerEMailList;

4.使用视图与计算字段

SELECT prod_id,
quantity,
item_price,
quantity*item_price AS expanded_price
FROM OrderItems
WHERE order_num = 20008;

CREATE VIEW OrderItemsExpanded AS
SELECT order_num,
prod_id,
quantity,
item_price,
quantity*item_price AS expanded_price
FROM OrderItems;

SELECT *
FROM OrderItemsExpanded
WHERE order_num = 20008;

免责声明：
1.编写此文是为了更好地学习MySQL的使用，如果损害了有关人的利益，请联系删除；
2.如果文中描述欠妥，请在评论中进行指正；
3.文字编写不易，若感觉有用，点赞收藏关注会让博主很开心哦；
4.此外，本文支持任何形式的转载，转载请注明出处，非常感谢！！！
本文源自：https://blog.csdn.net/testleaf/article/details/110095404
博客园cnblogs同号。

本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如若转载，请注明出处：http://www.coloradmin.cn/o/949888.html

如若内容造成侵权/违法违规/事实不符，请联系多彩编程网进行投诉反馈，一经查实，立即删除！

相关文章

前端：js实现提示框（自动消失）

前端：js实现提示框（自动消失）

效果&#xff1a; 代码&#xff1a; <!DOCTYPE html> <html lang"en"><head><meta charset"UTF-8"><meta http-equiv"X-UA-Compatible" content"IEedge"><meta name"viewport" content&q…
阅读更多...
正交实验如何进行方差分析？

正交实验如何进行方差分析？

一、案例介绍 欲研究温度&#xff08;℃&#xff09;、时间&#xff08;min&#xff09;、催化剂含量&#xff08;%&#xff09;对某物质转化率的影响&#xff0c;当前使用正交试验设计进行试验&#xff0c;试探究3个因素对转化率的影响是否显著&#xff0c;并找到能使转化率达…
阅读更多...
Source Insight查看源码

Source Insight查看源码

新建一个工程 Project -> Synchnorize Files 有可能找不到文件 Options -> File Type Option 查看或者设置快捷键
阅读更多...
IDEA新建SpringBoot项目时启动编译报错：Error:java: 无效的源发行版: 17

IDEA新建SpringBoot项目时启动编译报错：Error:java: 无效的源发行版: 17

文章目录 原因检查解决步骤修改jdk修改SpringBoot版本 原因 出现这种错误的原因可能是&#xff1a; 本机默认使用&#xff08;编译&#xff09;的jdk与该项目所使用的jdk版本不同。 jdk版本不适用于这个Idea&#xff0c;很典型的一个例子就是使用的Idea是2020的&#xff0c;而…
阅读更多...
C语言每日一练--------Day(11)

C语言每日一练--------Day(11)

本专栏为c语言练习专栏&#xff0c;适合刚刚学完c语言的初学者。本专栏每天会不定时更新&#xff0c;通过每天练习&#xff0c;进一步对c语言的重难点知识进行更深入的学习。 今日练习题关键字&#xff1a;找到数组中消失的数字 哈希表 &#x1f493;博主csdn个人主页&#xff…
阅读更多...
【java】【项目实战】[外卖七]短信验证码、手机短信登录开发

【java】【项目实战】[外卖七]短信验证码、手机短信登录开发

目录 一、发送短信 1 短信服务介绍 2 阿里云短信服务&#xff08;个人现在不太好申请了&#xff09; 2.1 介绍 2.2 注册账号 2.3 设置短信签名 2.4 设置短信模版 2.5 设置AccessKey 3 代码开发 3.1 导包 3.2 短信发送工具类SMSUtils 二、手机验证码登录 1 需求分析 …
阅读更多...
C++自创题目——第一期

C++自创题目——第一期

一、题目描述&#xff1a; 在一段时间内&#xff0c;到达港口的船有n艘&#xff0c;其中每艘船的信息包括:到达时间t(表示第t秒)&#xff0c;船上乘客数k&#xff0c;以及k名乘客的国籍。输出前3600s内每艘船上国籍种数&#xff0c;并输出国籍种数最少的船只的到达时间。 二、…
阅读更多...
ThreeJS模型加载动画——从下向上加载

ThreeJS模型加载动画——从下向上加载

从下向上动态加载模型，模型本身是由点-线-面组成，setDynamic动态控制模型每个point的位置，让模型出现一个动态加载的效果，如下图： 1、首先将模型压扁，获取point的position位置，然后设置y轴的高度为0，并将原始高度记录到modelPositons用于后面还原高度。 //将物…
阅读更多...
华为鲲鹏服务器

华为鲲鹏服务器

1.简介 鲲鹏通用计算平台提供基于鲲鹏处理器的TaiShan服务器、鲲鹏主板及开发套件。硬件厂商可以基于鲲鹏主板发展自有品牌的产品和解决方案&#xff1b;软件厂商基于openEuler开源OS以及配套的数据库、中间件等平台软件发展应用软件和服务&#xff1b;鲲鹏开发套件可帮助开发…
阅读更多...
前端刷题-深浅拷贝

前端刷题-深浅拷贝

深拷贝 function deepClone(obj) {if (obj null || typeof obj ! "object") {return obj;}if (obj instanceof Date) {return new Date(obj);}if (obj instanceof Array) {const cloneArray [];for (let i 0; i < obj.length; i) {cloneArray[i] deepClone(o…
阅读更多...
Android修改默认gradle路径

Android修改默认gradle路径

Android Studio每次新建项目&#xff0c;都会默认在C盘生成并下载gradle相关文件&#xff0c;由于C盘空间有限&#xff0c;没多久C盘就飘红了&#xff0c;于是就需要把gradle相关文件转移到其他盘 1、到C盘找到gradle文件 具体路径一般是&#xff1a;C:\Users\用户\ .gradle …
阅读更多...
Python+PIL+qrcode实现二维码自由—普通二维码+彩色二维码+logo二维码+动态二维码（附完整代码）

Python+PIL+qrcode实现二维码自由—普通二维码+彩色二维码+logo二维码+动态二维码（附完整代码）

有时候我们需要自己制作一个二维码&#xff0c;然后进行打印下来&#xff0c;或者说在二维码中提前写上一段话比如搞笑的话&#xff0c;然后印在衣服上&#xff0c;然后穿出去玩&#xff01;的&#x1f923; 那么今天我们分享一下制作二维码的几种方式&#xff1a; 哎&#x…
阅读更多...
Linux服务器安装部署MongoDB数据库 – 【无公网IP远程连接】

Linux服务器安装部署MongoDB数据库 – 【无公网IP远程连接】

文章目录 前言1.配置Mongodb源2.安装MongoDB数据库3.局域网连接测试4.安装cpolar内网穿透5.配置公网访问地址6.公网远程连接7.固定连接公网地址8.使用固定公网地址连接 前言 MongoDB是一个基于分布式文件存储的数据库。由 C 语言编写&#xff0c;旨在为 WEB 应用提供可扩展的高…
阅读更多...
word表格左侧边线明明有，但却不显示

word表格左侧边线明明有，但却不显示

如题&#xff0c;解决方法&#xff1a; 方案一&#xff1a; 1&#xff09;选中表格 2&#xff09;布局菜单--->自动调整 3&#xff09;自动调整中&#xff0c;选择“根据窗口自动调整表格” 4&#xff09;表格左侧边线就显示出来了。 方案二&#xff1a;把表格粘贴到新…
阅读更多...
macOS上制作arm64的jdk17镜像

macOS上制作arm64的jdk17镜像

公司之前一直用的openjdk17的镜像&#xff0c;docker官网可以直接下载&#xff0c;但是最近对接的一个项目&#xff0c;对方用的是jdk17&#xff0c;在对接的时候有加解密异常的问题&#xff0c;为了排查是不是jdk版本的问题&#xff0c;需要制作jdk17的镜像。docker官网上的第…
阅读更多...
【AI】《动手学-深度学习-PyTorch版》笔记（二十一）：目标检测

【AI】《动手学-深度学习-PyTorch版》笔记（二十一）：目标检测

AI学习目录汇总 1、简述 通过前面的学习，已经了解了图像分类模型的原理及实现。图像分类是假定图像中只有一个目标，算法上是对整个图像做的分类。 下面我们来学习“目标检测”，即从一张图像中找出需要的目标，并标记出位置。 2、边界框 边界框：bounding box，就是一个方…
阅读更多...
走进Linux系统

走进Linux系统

1.开机关机和基本目录介绍 /www 目录:存放服务器网站相关资源&#xff0c;环境&#xff0c;网站的项目
阅读更多...
【GO】LGTM_Grafana_Tempo(2)_官方用例改后实操

【GO】LGTM_Grafana_Tempo(2)_官方用例改后实操

最近在尝试用 LGTM 来实现 Go 微服务的可观测性&#xff0c;就顺便整理一下文档。 Tempo 会分为 4 篇文章&#xff1a; Tempo 的架构官网测试实操跑通gin 框架发送 trace 数据到 tempogo-zero 微服务框架使用发送数据到 tempo 根据官方文档实操跑起来 tempo&#xff0c;中间根…
阅读更多...
数据分析师职业发展道路,工作内容是什么？

数据分析师职业发展道路,工作内容是什么？

很多同学问&#xff0c;参加数据分析就业班后之的就业发展道路是怎样的&#xff0c;工作又能做什么呢&#xff1f; 市面上的常见的工作类型有有运营类、技术类及分析类等&#xff0c;可以根据自己的意愿去做适合自己的工作&#xff0c;但是任何工作其实都是需要一技之长。…
阅读更多...
对 K8s Pod 安全有多少认识？

对 K8s Pod 安全有多少认识？

写在前面 简单整理&#xff0c;博文内容涉及&#xff1a; PSP 的由来PSA 的发展PSA 使用认知 不涉及使用&#xff0c;用于了解 Pod 安全 API 资源理解不足小伙伴帮忙指正 对每个人而言&#xff0c;真正的职责只有一个&#xff1a;找到自我。然后在心中坚守其一生&#xff0c;全…
阅读更多...
推荐文章
最新文章

Copyright @ 2022~2023