原文链接： https://anran758.github.io/blog/2022/05/16/mysql-note/
由于自考的实践要求有需要用到 mysql 进行考核，故记录一下在 mac 环境下试手的笔记。
初始环境
首先在 mysql 官网中下载你想要的版本。可以直接下载 dmg 安装包，按照安装指示一步一步安装，并设置 mysql 的密码。
下载完毕后，一般情况下直接通过命令行使用 mysql 命令会找不到对应的命令：
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➜ ~ mysql -v
zsh: command not found: mysql
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因此需要对当前的命令行工具配置对应的环境变量，比如笔者使用的是 zsh，则打开 ~/.zshrc 文件添加以下配置:
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export PATH=${PATH}:/usr/local/mysql/bin/
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若使用 bash 的用户同理，直接在 ~/.bashrc 添加相同代码。添加完毕后通过 source 命令重新加载对应的环境变量: source ~/.zshrc
接着就可以在命令行直接使用 mysql 了。输入 mysql -u root -p 登录 mysql，密码是在安装阶段时设置的密码。
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➜ ~ mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 13
Server version: 8.0.29 MySQL Community Server - GPL
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
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数据库操作
DATABASE 可以不区分大小写，但只能要么全小写，要么全大写。一般会将这些参数用大写写出。
创建数据库
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-- 还可以通过 DEFAULT CHARACTER SET 选项设置默认的编码集
mysql> CREATE DATABASE DANNY_DATABASE;
Query OK, 1 row affected (0.01 sec)
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查看现有的数据库
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mysql> SHOW DATABASES;
+----------------------------+
| Database |
+----------------------------+
| information_schema |
| DANNY_DATABASE |
| mysql |
| performance_schema |
| sys |
+----------------------------+
6 rows in set (0.00 sec)
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切换到指定数据库
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mysql> USE DANNY_DATABASE
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数据库的查看与删除
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-- 创建数据库: 准备稍后移除的数据库
mysql> CREATE DATABASE DANNY_DATABASE_WAIT_DELETE;
Query OK, 1 row affected (0.01 sec)
mysql> SHOW DATABASES;
+----------------------------+
| Database |
+----------------------------+
| information_schema |
| DANNY_DATABASE |
| DANNY_DATABASE_WAIT_DELETE |
| mysql |
| performance_schema |
| sys |
+----------------------------+
6 rows in set (0.00 sec)
-- 删除数据库
mysql> DROP DATABASE DANNY_DATABASE_WAIT_DELETE;
Query OK, 0 rows affected (0.02 sec)
mysql> SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema |
| DANNY_DATABASE |
| mysql |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)
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查看当前使用的数据库
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-- 未选择的情况下
mysql> SELECT DATABASE();
+----------------+
| DATABASE() |
+----------------+
| null |
+----------------+
1 row in set (0.00 sec)
-- 切换指定数据库
use DANNY_DATABASE;
mysql> SELECT DATABASE();
+----------------+
| DATABASE() |
+----------------+
| danny_database |
+----------------+
1 row in set (0.00 sec)
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数据表操作
创建数据表
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-- 创建名为 customers 的数据表
mysql> CREATE TABLE IF NOT EXISTS customers(
-> cust_id INT NOT NULL AUTO_INCREMENT,
-> cust_name CHAR(50) NOT NULL,
-> cust_sex CHAR(1) NOT NULL DEFAULT 0,
-> cust_address CHAR(50) NULL,
-> cust_contact CHAR(50) NULL,
-> PRIMARY KEY(cust_id)
-> );
Query OK, 0 rows affected (0.11 sec)
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其中 IF NOT EXISTS 参数是可选的，它的意思为若 customers 表不存在则创建它。
查看数据表与表列
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-- 查看当前用户在当前数据库中可以访问的数据表
mysql> SHOW TABLES;
+--------------------------+
| Tables_in_danny_database |
+--------------------------+
| customers |
+--------------------------+
1 rows in set (0.00 sec)
-- 查看指定数据表中列的信息
-- DESC customers; 等价于如下命令
mysql> SHOW COLUMNS from customers;
+--------------+-------------+------+-----+-----------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+-----------+----------------+
| cust_id | int(11) | NO | PRI | NULL | auto_increment |
| cust_name | char(50) | NO | | NULL | |
| cust_sex | char(1) | NO | | 0 | |
| cust_address | char(50) | YES | | NULL | |
| cust_contact | char(50) | YES | | NULL | |
+--------------+-------------+------+-----+-----------+----------------+
5 rows in set (0.00 sec)
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删除数据表
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-- 添加一个数据表用于演示删除
mysql> CREATE TABLE IF NOT EXISTS customers_1(
-> cust_id INT NOT NULL AUTO_INCREMENT,
-> cust_name CHAR(50) NOT NULL,
-> cust_sex CHAR(1) NOT NULL DEFAULT 0,
-> cust_address CHAR(50) NULL,
-> cust_contact CHAR(50) NULL,
-> PRIMARY KEY(cust_id)
-> );
Query OK, 0 rows affected (0.11 sec)
-- 查看当前的数据表
mysql> SHOW tables;
+--------------------------+
| Tables_in_danny_database |
+--------------------------+
| customers |
| customers_1 |
+--------------------------+
2 rows in set (0.00 sec)
-- 删除指定数据表
mysql> DROP TABLES customers_1;
Query OK, 0 rows affected (0.02 sec)
mysql> SHOW tables;
+--------------------------+
| Tables_in_danny_database |
+--------------------------+
| customers |
+--------------------------+
1 row in set (0.00 sec)
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数据表添加新列
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-- 插入新列
mysql> alter TABLE customers
-> ADD COLUMN cust_city char(10) NOT NULL DEFAULT 'guangzhou' AFTER cust_sex;
Query OK, 0 rows affected (0.06 sec)
Records: 0 Duplicates: 0 Warnings: 0
-- 确认表列状态
mysql> SHOW COLUMNS from customers;
+--------------+-------------+------+-----+-----------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+-----------+----------------+
| cust_id | int(11) | NO | PRI | NULL | auto_increment |
| cust_name | char(50) | NO | | NULL | |
| cust_sex | char(1) | NO | | 0 | |
| cust_city | char(10) | NO | | guangzhou | |
| cust_address | char(50) | YES | | NULL | |
| cust_contact | char(50) | YES | | NULL | |
+--------------+-------------+------+-----+-----------+----------------+
6 rows in set (0.00 sec)
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数据表修改表列
修改整列: 将列名 cust_sex 修改 sex，并修改默认值
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mysql> alter TABLE customers
-> CHANGE COLUMN cust_sex sex char(1) NULL DEFAULT 'M';
Query OK, 0 rows affected (0.04 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> SHOW COLUMNS from customers;
+--------------+-------------+------+-----+-----------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+-----------+----------------+
| cust_id | int(11) | NO | PRI | NULL | auto_increment |
| cust_name | char(50) | YES | | NULL | |
| sex | char(1) | YES | | M | |
| cust_city | char(10) | NO | | guangzhou | |
| cust_address | char(50) | YES | | NULL | |
| cust_contact | char(50) | YES | | NULL | |
+--------------+-------------+------+-----+-----------+----------------+
6 rows in set (0.00 sec)
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仅修改列的类型
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mysql> ALTER TABLE customers
-> MODIFY COLUMN cust_address varchar(50);
Query OK, 0 rows affected (0.06 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> show COLUMNS from customers;
+--------------+-------------+------+-----+-----------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+-----------+----------------+
| cust_id | int(11) | NO | PRI | NULL | auto_increment |
| cust_name | char(50) | YES | | NULL | |
| sex | char(1) | YES | | M | |
| cust_city | char(10) | NO | | guangzhou | |
| cust_address | varchar(50) | YES | | NULL | |
| cust_contact | char(50) | YES | | NULL | |
+--------------+-------------+------+-----+-----------+----------------+
6 rows in set (0.00 sec)
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修改指定列的指定字段
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mysql> ALTER TABLE customers
-> ALTER COLUMN cust_city SET DEFAULT 'shenzhen';
Query OK, 0 rows affected (0.03 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> SHOW COLUMNS from customers;
+--------------+-------------+------+-----+----------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+----------+----------------+
| cust_id | int(11) | NO | PRI | NULL | auto_increment |
| cust_name | char(50) | YES | | NULL | |
| sex | char(1) | YES | | M | |
| cust_city | char(10) | NO | | shenzhen | |
| cust_address | varchar(50) | YES | | NULL | |
| cust_contact | char(50) | YES | | NULL | |
+--------------+-------------+------+-----+----------+----------------+
6 rows in set (0.00 sec)
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移除数据表列： 移除 cust_contact 数据表项
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mysql> ALTER TABLE danny_database.customers
-> DROP COLUMN cust_contact;
Query OK, 0 rows affected (0.04 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> SHOW COLUMNS from customers;
+--------------+-------------+------+-----+----------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+----------+----------------+
| cust_id | int(11) | NO | PRI | NULL | auto_increment |
| cust_name | char(50) | YES | | NULL | |
| sex | char(1) | YES | | M | |
| cust_city | char(10) | NO | | shenzhen | |
| cust_address | varchar(50) | YES | | NULL | |
+--------------+-------------+------+-----+----------+----------------+
5 rows in set (0.00 sec)
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数据项操作
添加数据
默认情况下在命令行中 mysql 是不能直接插入中文的，这个跟字符集有关。可输入下面命令修改数据库或表的字符集:
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-- 设置名为 danny_database 的数据库字符集
ALTER DATABASE danny_database character SET utf8;
-- 设置名为 customers 的数据库表字符集 (Tip: 若数据库已经被设置为 utf8, 则无需再设置表的字符集)
ALTER TABLE customers convert to character SET utf8;
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为数据表插入数据，显式设置字段
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mysql> INSERT INTO danny_database.customers(cust_id, cust_name, sex, cust_address)
-> VALUES(901, '张三', DEFAULT, '广州市');
Query OK, 1 row affected (0.02 sec)
mysql> INSERT INTO danny_database.customers(cust_id, cust_name, sex, cust_address)
-> VALUES(0, '李四', DEFAULT, '广州市');
Query OK, 1 row affected (0.01 sec)
mysql> select * from customers;
+---------+-----------+------+-----------+--------------+
| cust_id | cust_name | sex | cust_city | cust_address |
+---------+-----------+------+-----------+--------------+
| 901 | 张三 | M | shenzhen | 广州市 |
| 902 | 李四 | M | shenzhen | 广州市 |
+---------+-----------+------+-----------+--------------+
2 rows in set (0.00 sec)
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由于 cust_id 是自增的，因此可以将此字段的值设置为 0 或 NULL 会自动自增。上例 “李四” 的 cust_id 在创建后就被自增为 902。
还可以通过 SET 语句设置部分值：
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mysql> INSERT INTO danny_database.customers SET cust_name='王五', cust_address='武汉市', sex=DEFAULT;
Query OK, 1 row affected (0.00 sec)
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查询数据
可通过 SELECT 语句查询数据：
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mysql> SELECT * FROM customers;
+---------+-----------+------+-----------+--------------+
| cust_id | cust_name | sex | cust_city | cust_address |
+---------+-----------+------+-----------+--------------+
| 901 | 张三 | M | shenzhen | 广州市 |
| 902 | 李四 | M | shenzhen | 广州市 |
| 903 | 王五 | M | shenzhen | 武汉市 |
+---------+-----------+------+-----------+--------------+
3 rows in set (0.00 sec)
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仅展示指定字段：
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+---------+-----------+------+
| cust_id | cust_name | sex |
+---------+-----------+------+
| 901 | 张三 | M |
| 902 | 李四 | M |
| 903 | 王五 | M |
+---------+-----------+------+
3 rows in set (0.00 sec)
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通过 WHERE 子句设置查询条件，筛选出符合查询条件的数据：
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mysql> SELECT cust_id,cust_name,cust_address FROM customers
-> WHERE cust_address="广州市";
+---------+-----------+--------------+
| cust_id | cust_name | cust_address |
+---------+-----------+--------------+
| 901 | 张三 | 广州市 |
| 902 | 李四 | 广州市 |
+---------+-----------+--------------+
2 rows in set (0.00 sec)
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删除数据
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-- 添加几项测试数据
mysql> INSERT INTO danny_database.customers(cust_id, cust_name, sex, cust_address)
-> VALUES(1, 'test1', DEFAULT, '深圳市');
Query OK, 1 row affected (0.02 sec)
mysql> select * from customers;
+---------+-----------+------+-----------+--------------+
| cust_id | cust_name | sex | cust_city | cust_address |
+---------+-----------+------+-----------+--------------+
| 1 | test1 | M | shenzhen | 深圳市 |
| 901 | 张三 | M | shenzhen | 广州市 |
| 902 | 李四 | M | shenzhen | 广州市 |
| 903 | 王五 | M | shenzhen | 武汉市 |
+---------+-----------+------+-----------+--------------+
4 rows in set (0.00 sec)
-- 删除表数据
mysql> DELETE FROM customers
-> WHERE cust_id=1;
Query OK, 1 row affected (0.02 sec)
mysql> select * from customers;
+---------+-----------+------+-----------+--------------+
| cust_id | cust_name | sex | cust_city | cust_address |
+---------+-----------+------+-----------+--------------+
| 901 | 张三 | M | shenzhen | 广州市 |
| 902 | 李四 | M | shenzhen | 广州市 |
| 903 | 王五 | M | shenzhen | 武汉市 |
+---------+-----------+------+-----------+--------------+
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更新数据
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-- 更新数据
mysql> UPDATE customers SET cust_address="深圳市" WHERE cust_name="李四";
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> SELECT * FROM customers;
+---------+-----------+------+-----------+--------------+
| cust_id | cust_name | sex | cust_city | cust_address |
+---------+-----------+------+-----------+--------------+
| 901 | 张三 | M | shenzhen | 广州市 |
| 902 | 李四 | M | shenzhen | 深圳市 |
| 903 | 王五 | M | shenzhen | 武汉市 |
+---------+-----------+------+-----------+--------------+
3 rows in set (0.00 sec)
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实践
以一个 eShop 的需求为例做个简单的测试吧。
创建 eshop 数据库
在 MySQL 中创建一个名为 eshop 的数据库，选择字符集为 utf8mb4
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mysql> CREATE DATABASE IF NOT EXISTS eshop DEFAULT CHARACTER SET utf8mb4;
Query OK, 1 row affected (0.01 sec)
mysql> SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema |
| DANNY_DATABASE |
| eshop |
| mysql |
| performance_schema |
| sys |
+--------------------+
6 rows in set (0.01 sec)
-- 切换数据库
mysql> use eshop;
Database changed
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创建数据表及相关记录
相关表信息如下
表名：用户(t_user)
| 字段名 |
类型 |
大小 |
| 用户ID (id) |
自增类型 |
|
| 姓名 (user_name) |
文本 |
50，非空 |
| 联系电话 (phone_no) |
文本 |
20，非空 |
表名：商品（product）
| 字段名 |
类型 |
大小 |
| 商品ID（id） |
自增类型 |
|
| 商品名称(product_name) |
文本 |
50，非空 |
| 价格(price) |
数值类型 |
（整数位9位，小数位2位），非空 |
表名：购物车 (shopping_cart)
| 字段名 |
类型 |
大小 |
| 用户id（user_id） |
整数 |
非空，主键，参考用户表主键 |
| 商品id(product_id) |
整数 |
非空，主键，参考商品表主键 |
| 商品数量(quantity) |
整数 |
非空 |
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-- 用户表
mysql> CREATE TABLE IF NOT EXISTS t_user(
-> `id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> `user_name` CHAR(50) NOT NULL,
-> `phone_no` CHAR(20) NOT NULL
-> );
Query OK, 0 rows affected (0.06 sec)
-- 商品表
mysql> CREATE TABLE IF NOT EXISTS product(
-> `id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> `product_name` CHAR(50) NOT NULL,
-> `price` DOUBLE(9, 2)
-> );
Query OK, 0 rows affected (0.06 sec)
-- 购物车
mysql> CREATE TABLE IF NOT EXISTS shopping_cart(
-> `user_id` INT NOT NULL,
-> `product_id` INT NOT NULL,
-> `quantity` INT NOT NULL,
-> PRIMARY KEY(`user_id`, `product_id`)
-> );
Query OK, 0 rows affected (0.05 sec)
-- 查看数据表
mysql> show tables;
+-----------------+
| Tables_in_eshop |
+-----------------+
| product |
| shopping_cart |
| t_user |
+-----------------+
3 rows in set (0.00 sec)
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录入用户数据
用户信息
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1;张三; 13333333333;
2;李四; 13666666666
3;王五; 13888888888
4;赵六; 13999999999
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商品信息
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1; C++程序设计教程; 45.5
2; 数据结构; 33.7
3; 操作系统; 51
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购物车
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1; 1; 5
1; 2; 3
2; 3; 6
2; 4; 8
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录入数据：
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-- 插入用户表数据
mysql> INSERT INTO t_user
-> (id, user_name, phone_no)
-> VALUES
-> (1, '张三', '13333333333'),
-> (2, '李四', '13666666666'),
-> (3, '王五', '13888888888'),
-> (4, '赵六', '13999999999');
Query OK, 4 rows affected (0.02 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM t_user;
+----+-----------+-------------+
| id | user_name | phone_no |
+----+-----------+-------------+
| 1 | 张三 | 13333333333 |
| 2 | 李四 | 13666666666 |
| 3 | 王五 | 13888888888 |
| 4 | 赵六 | 13999999999 |
+----+-----------+-------------+
4 rows in set (0.00 sec)
-- 插入「商品信息」
mysql> INSERT INTO product
-> (id, product_name, price)
-> VALUES
-> (1, 'C++程序设计教程', 45.5),
-> (2, '数据结构', 33.7),
-> (3, '操作系统', 51);
Query OK, 3 rows affected (0.01 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM product;
+----+-----------------------+-------+
| id | product_name | price |
+----+-----------------------+-------+
| 1 | C++程序设计教程 | 45.50 |
| 2 | 数据结构 | 33.70 |
| 3 | 操作系统 | 51.00 |
+----+-----------------------+-------+
3 rows in set (0.00 sec)
-- 插入购物车
mysql> INSERT INTO shopping_cart
-> (user_id, product_id, quantity)
-> VALUES
-> (1, 1, 5),
-> (1, 2, 3),
-> (2, 3, 6),
-> (2, 4, 8);
Query OK, 4 rows affected (0.01 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM shopping_cart;
+---------+------------+----------+
| user_id | product_id | quantity |
+---------+------------+----------+
| 1 | 1 | 5 |
| 1 | 2 | 3 |
| 2 | 3 | 6 |
| 2 | 4 | 8 |
+---------+------------+----------+
4 rows in set (0.00 sec)
|
数据的查询与更新
使用 SQL 语句列出「张三」购买商品清单信息，以购买数量升序排列：
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mysql> SELECT u.user_name, p.product_name, u.phone_no, p.price, s.quantity FROM t_user u, product p, shopping_cart s
-> WHERE u.user_name="张三" AND u.id = s.user_id AND p.id = s.product_id
-> ORDER BY quantity asc
-> LIMIT 100;
+-----------+-----------------------+-------------+-------+----------+
| user_name | product_name | phone_no | price | quantity |
+-----------+-----------------------+-------------+-------+----------+
| 张三 | 数据结构 | 13333333333 | 33.70 | 3 |
| 张三 | C++程序设计教程 | 13333333333 | 45.50 | 5 |
+-----------+-----------------------+-------------+-------+----------+
2 rows in set (0.01 sec)
|
使用 SQL 语句选出李四购买商品的总价：
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mysql> SELECT u.user_name, p.product_name, p.price, s.quantity, p.price*s.quantity AS total_price FROM t_user u, product p, shopping_cart s
-> WHERE u.user_name="李四" AND u.id = s.user_id AND p.id = s.product_id
-> LIMIT 100;
+-----------+--------------+-------+----------+-------------+
| user_name | product_name | price | quantity | total_price |
+-----------+--------------+-------+----------+-------------+
| 李四 | 操作系统 | 51.00 | 6 | 306.00 |
+-----------+--------------+-------+----------+-------------+
1 row in set (0.00 sec)
|
使用 SQL 语句列出购买数量排前两位的商品名称：
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mysql> SELECT p.product_name, p.price, s.quantity FROM product p, shopping_cart s
-> WHERE p.id = s.product_id
-> ORDER BY quantity desc
-> LIMIT 2;
+-----------------------+-------+----------+
| product_name | price | quantity |
+-----------------------+-------+----------+
| 操作系统 | 51.00 | 6 |
| C++程序设计教程 | 45.50 | 5 |
+-----------------------+-------+----------+
2 rows in set (0.00 sec)
|
忘记密码
若忘记数据库密码后可通过 mysqld_safe 来修改密码：
-
在系统偏好设置中关闭 mysql 服务
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打开终端，输入命令:
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➜ ~ cd /usr/local/mysql/bin
➜ ~ sudo su
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-
命令行变成以 sh-3.2# 开头后继续输入命令:
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sh-3.2# ./mysqld_safe --skip-grant-tables &
mysqld_safe Logging to '/usr/local/mysql/data/DannydeMBP.err'.
mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data
|
-
新开个命令行窗口，进入 mysql:
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➜ ~ /usr/local/mysql/bin/mysql
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 30
Server version: 5.7.31
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
mysql> use mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
|
-
更新密码
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mysql> update user set authentication_string=password('admin') where Host='localhost' and User='root';
Query OK, 1 row affected, 1 warning (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 1
|
-
输入 exit 命令退出 mysql，查出 mysqld_safe 进程号并杀掉:
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mysql> exit
Bye
➜ ~ ps -ax | grep mysql
8553 ttys004 0:00.03 /bin/sh ./mysqld_safe --skip-grant-tables
8623 ttys004 0:00.92 /usr/local/mysql-5.7.31-macos10.14-x86_64/bin/mysqld --basedir=/usr/local/mysql-5.7.31-macos10.14-x86_64 --datadir=/usr/local/mysql-5.7.31-macos10.14-x86_64/data --plugin-dir=/usr/local/mysql-5.7.31-macos10.14-x86_64/lib/plugin --user=mysql --skip-grant-tables --log-error=host-3-187.can.danny1.network.err --pid-file=host-3-187.can.danny1.network.pid
# 杀掉 mysql 的进程
➜ ~ kill -9 8553
➜ ~ kill -9 8623
|
-
此时返回系统偏好设置中看到 mysql 被关闭后就算正确退出了。接着继续输入 mysql -u root -p 命令连接数据库，再输入刚才修改的密码即可。
参考资料
本文转自： https://anran758.github.io/blog/2022/05/16/mysql-note/
本站仅做收录，版权归原作者所有。
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