The basic concept and installation of Mysql database-super detailed! ! !

One, the basic concept of the database

1. Data

• Symbol record
• Including data, text, graphics, images, sounds, file records, etc.
• Store in a unified format in the form of "records"

2. Table

• Organize different records together
• Used to store specific data

3. Database

• A collection of tables is a warehouse for storing data
• A collection of related data stored in a certain organization
  

4. Database Management System (DBMS)

• It is a system software that realizes effective organization, management and access to database resources

5. Database system

• It is a man-machine system consisting of hardware, os, database, DBMS, application software and database users
• Users can operate the database through DBMS or applications
  

2. History of database system development

1. The first generation database

• Since the 1960s, the first generation of database systems came out
• It is a database system of hierarchical model and network model
• Provides strong support for unified management and sharing of data

2. The second generation database

• In the early 1970s, the second generation of databases-relational databases began to appear
• In the early 1980s, IBM's relational database system DB2 came out, and began to gradually replace hierarchical and mesh model databases, becoming the mainstream of the industry
• So far, relational database systems have occupied the main position of database applications

3. The third generation database

• Since the 1980s, new database systems adapting to different fields have continuously emerged. Object-oriented database systems have strong practicability and wide adaptability.
• In the late 1990s, a situation in which multiple database systems jointly supported applications was formed
• Some new elements have been added to the mainstream database system
• For example, the "relation-object" database model supported by Oracle

3. Today's mainstream databases

1. Introduction to mainstream databases

SQL Server (product of Microsoft Corporation)

• For Windows operating system
• Simple and easy to use

Oracle (Oracle company product)

• For all major platforms
• Safe, perfect, complicated operation

DB2 (product of IBM)

• For all major platforms
• Large, safe and complete

MySQL (acquired by Oracle)

• Free, open source, small size
  

2. Relational database

Relational database-1

• Relational database system is a database system based on relational model
• The data structure of the relational model uses a simple and easy to understand two-dimensional data table
• The relational model can be represented by a simple "Entity-Relationship" (ER) diagram
• The ER diagram contains three elements: entity (data object), relationship and attribute
  

Relational database-2
entities

• Also called an instance, it corresponds to an "event" or "thing" that can be distinguished from other objects in the real world
  • Such as bank customers, bank accounts, etc.

Attributes

• A certain characteristic of an entity, an entity can have multiple attributes
  • For example, each entity in the "bank customer" entity set has attributes such as name, address, and telephone number

contact

• Correspondence between entity sets is called connection, also called relationship
  • For example, there is a "savings" relationship between bank customers and bank accounts

The collection of all entities and their connections constitutes a relational database

Relational database-3

• The storage structure of the relational database is a two-dimensional table
• In each two-dimensional table
  • Each row is called a record, used to describe the information of an object
  • Each column is called a field, used to describe an attribute of the object
    

3. Relational database applications

Relational Database

• Oracle，MySQL
• SQLServer、Sybase
• lnformix、access
• DB2、FoxPRO

Application examples

• 12306 User Information System
• Taobao account system
• Unicom mobile phone number information system
• Bank User Account System
• Website User Information System

4. Introduction to non-relational databases

Non-relational databases are also called NoSQL (Not Only SQL)

The stored data is not based on the relational model and does not require a fixed table format

Advantages of non-relational databases

• The database can be read and written with high concurrent
• Efficient storage and access to massive data
• Database has high scalability and high availability

Commonly used non-relational databases: Redis, mongoDB, etc.

5. Introduction to MySQL database

• A popular open source relational database
• Oracle products
• Comply with GPL agreement, free trial and modification

Features:

• Excellent performance and stable service
• Open source, no copyright restrictions, low cost
• Multi-threaded, multi-user
• Based on C/S (client/server) architecture
• Safe and reliable

6. MySQL Business Edition and Community Edition

• MySQL Business Edition is developed and maintained by MySQL AB, and requires payment to use
• MySQL Community Edition is developed and maintained by MySQL developers and enthusiasts scattered all over the world, and can be used for free

The difference between the two:

• The commercial version has stricter organization management and testing and will be more stable than the community version
• The commercial version does not comply with the GPL, and the community version complies with the GPL and can be used for free
• The commercial version can get 7*24 hours of service, while the community version does not

7. MySQL product camp

• The first camp: 5.0-5.1 camp, can be said to be the continuation of early products

• The second camp: The 5.4-5.7 camp integrates storage engines developed by MySQL AB, the community, and third-party companies to improve performance

• The third camp: 6.0-7.1 camp, which is the MySQL Cluster version, developed to meet the needs of database clustering in the new era

  • Download URL
    http://www.dev.mysql.com/downloads

Fourth, install Mysql5.7 database

Prepare the installation package Mysql package

1. Install the dependent package

[root@server1 ~]#yum -y install \
ncurses \
ncurses-devel \
bison \
cmake

2. Create a non-loginable user

[root@server1 ~]# useradd -s /sbin/nologin mysql

3. Unzip the Mysql package

[root@server1 ~]#tar -zxvf mysql-boost-5.7.20.tar.gz

4. cmake configuration

[root@server1 ~]#cd mysql-5.7.20/
[root@server1 mysql-5.7.20]# cmake \
-DCMAKE_INSTALL_PREFIX=/usr/local/mysql \              #安装目录 安装路径
-DMYSQL_UNIX_ADDR=/usr/local/mysql/mysql.sock \   #指定套接字文件的存储路径套接字：客户端访问mysql数据库的一个接口
-DSYSCONFDIR=/etc \                                     #配置my. cnf的目录 配置文件路径，（根目录）
-DSYSTEMD_PID_DIR=/usr/local/mysql \          #主服务进程所在路径 （进程文件目录）
-DDEFAULT_CHARSET=utf8 \                           #默认字符集
-DDEFAULT_COLLATION=utf8_general_ci \      #默认编码
-DWITH_INNOBASE_STORAGE_ENGINE=1 \     #启用InnoDB引擎
-DWITH_ARCHIVE_STORAGE_ENGINE=1 \        #启用ARCHIVE引擎
-DWITH_BLACKHOLE_STORAGE_ENGINE=1 \   #启用BLACKHOLE引擎
-DWITH_PERFSCHEMA_STORAGE_ENGINE=1 \  #启用perfschema引擎
-DMYSQL_DATADIR=/usr/local/mysql/data \    #数据存储路径  （数据库目录）
-DWITH_BOOST=boost \              #boost库是为C++语言标准库提供扩展的一些C++程序库的总称
-DWITH_SYSTEMD=1                 #这是mysql5.7原生支持systemd的选项，如果用systemctl启动，就必须开启

5. Compile and install

make && make install

6. Edit the configuration file

[root@server1 ~]# vi /etc/my.cnf

[client]      客户端
port = 3306  访问端口
default-character-set = utf8  默认字符集
socket = /usr/local/mysql/mysql.sock  套接字
[mysql]    运行用户
port = 3306  运行端口
default-character-set = utf8
socket = /usr/local/mysql/mysql.sock
[mysqld]  程序
user = mysql   运行用户
basedir = /usr/local/mysql  根目录
datadir = /usr/local/mysql/data   用户目录
port = 3306  
character_set_server = utf8
pid-file = /usr/local/mysql/mysqld.pid   服务器配置字符
socket = /usr/local/mysql/mysql.sock   进程文件
server-id = 1
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_AUTO_VALUE_ON_ZERO,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,PIPES_AS_CONCAT,ANSI_QUOTES

7. Database authority configuration, owner, group

[root@server1 mysql-5.7.20]# chown -R mysql:mysql /usr/local/mysql/
[root@server1 mysql-5.7.20]# chown mysql:mysql /etc/my.cnf

8. Initialize the database

[root@server1 ~]# mysqld \
--initialize-insecure \             #生成一个空密码，不配置系统会自动生成一个密码
--user=mysql \
--basedir=/usr/local/mysql \
--datadir=/usr/local/mysql/data

9. Copy files and start the service

[root@server1 ~]# cd /usr/local/mysql/
[root@server1 mysql]# cp usr/lib/systemd/system/mysqld.service /usr/lib/systemd/system
[root@server1 mysql]# cd
[root@server1 ~]# systemctl enable mysqld
[root@server1 ~]# systemctl start mysqld
[root@server1 ~]# systemctl status mysqld

10. Set a password

[root@server1 ~]# mysqladmin -uroot -p password 'fa123'
[root@server1 ~]# mysql -uroot -p