MySQL original ecological SQL statement (not yet continued)

MySQL Introduction

• MySQL is a relational database management system, where relational databases store data in different tables rather than putting all of the data in a large warehouse, which increases speed and increases flexibility. Because MySQL is an open source software, it can greatly reduce the total cost of ownership. In the future, MySQL may also become a fee-charging software, of course, that is the future of the matter. Now let's introduce MySQL's original SQL statement

Set up your MySQL account locally

• Create a My.ini file
  [Mysqld]
  Character-set-server=utf8 #库的编码模式设置为utf8
  Collation-server=utf8_general_ci
  [Client]
  Default-character-set=utf8
  User=root # account name is root
  [MySQL]
  Default-character-set=utf8 # Every library created, the default encoding is UTF8
  Add the MySQL installation target file to the environment variable and operate the MySQL database directly in cmd. No account password is required to open MySQL, default read from profile My.ini to set mode to strict mode

  set global sql_mode= "strict_trans_tables,only_full_group_by"; #修改为严格模式,只能查看到分组后的字段,配合聚合函数.其余操作会报错例如:select * from emo group by post;  #会报错,原因是分组之后在去查看某一条数据毫无意义强调: 模式设置为严格模式需要重新启动MYSQL

  Set MySQL to run automatically in the background

MySQL original SQL statement library: essentially a folder

• Increase
  Create database folder name CharSet UTF8;
• Delete
  drop database folder name;
• Modify
  Alter DATABASE folder name CharSet GBK; #修改指的是修改文件夹的编码方式
• View
  show databases; # View All folders
  Show create database folder name; #查看指定文件夹表: A file
• Increase
• Delete
• Modify
• View

MySQL original ecological SQL statement (not yet continued)