Operation of the 6-12mysql library

Various classifications of the 1,mysql library:

nformation_schema: Virtual Library, does not occupy disk space, storage is the database startup parameters, such as user table information, column information, permission information, character information and so on.
performance_schema: MySQL 5.5 has started to add a database: Mainly used to collect database server performance parameters, record the processing of query requests for various events, locks and other phenomena.
MySQL: Authorization library, the primary storage System user's permissions information.
Test: The database automatically created by the MySQL database system.

2, the various operations of the library:

Create library name CharSet UTF8;

SOS Grammar help CREATE database;

Naming conventions for databases:

   Can be used by letters, numbers, underscores, @, #, $ case-   sensitive   uniqueness   cannot use keywords such as create select   cannot use numbers up to   128 bits maximum  # It's basically the same as a python or JS naming convention.

3, the specific various operations:

Create Database db1; #查看所在的库 Select Database (); #选择数据库  Use Database name # Delete database DROP DATABASE database name; # Modify Database Alter database db1 charset UTF8;

4. Understanding Content

the SQL language is primarily used to access data, query data, update data, and manage relational database systems, which are developed by IBM. There are 3 types of SQL languages:1, DDL statements,    DROPALTER2, DML statement    database manipulation language: Inserting data Insert, Deleting data delete, updating data update, querying data Select3, DCL Statement    Database Control Language: For example, controlling access rights for users grant,REVOKE

　　

Operation of the 6-12mysql library